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[dichotomous1]

Hi,
I've had this issue for the past couple of years and not sure the cause.  I curate a list of audio tracks to play for the day, drop em in playing now, plays fine but then random times, playback stops at the end of a track and all tracks in Playing Now disappear except for the last track played.

I've never been at the computer when this happens.  It doesn't happen every day, but something like 40% of the time. I've not noticed any consistency other than it always occurs late in the day after playing for at least 4 hours.

I know I can recover the deleted track listing.  I would like to know whats causing it.
Also, what's u[pp with the Recent Playing Now's smart playlist now updating on a regular basis?

Could it be the same deamon that alters the Volume even when your cursor isnt even near the slider?



J

PS, I'm running MC 25 on a late 2009  27" iMac. OS 10.13.6

[RoderickGI]

Are your files on an external drive or a NAS?
Do you have Auto Import running in the background?
Do you have "Fix Broken Links" checked in Auto Import?

[dichotomous1]

Yes, files are stored on a NAS (Synology)
Auto Import is not On
Fix Broken Links is On

MC version 25.0.128   (Reverted from MC 26 as the program would crash upon startup on both iMac and MacBook Pro)


I happened to be sitting at the comp when it just occurred.  Attached is the last 4 pages of the log. Full log avail if needed.

[RoderickGI]

Well, even with Auto Import off, I would guess if your NAS drives go to sleep (spin down) and MC tries to play the next track, which it tries to access before the current one finishes, then MC finds the file isn't available and removes it from Playing Now. MC then repeats the process for all remaining files in Playing Now, finds them all unavailable, and removes them from Playing Now.

You need to stop your NAS from spinning down drives so often, when it is regularly serving up files, if the above is the case. I suspect a NAS setting for that.

Normally MC does wait for a remote drive to spin up. But if Playing Now is already populated it may wait for a shorter time, or even expect the drive to be available, as it was when the files were added to Playing Now.


Confirmation of the above is that Recent Playing Now's Smartlist is updating regularly. I suspect that each time MC tries to access the NAS and can't, and so removes a file from Playing Now, it creates a Recent Playing Now record. How many has it been creating? Would the number match approximately the number of unplayed files in Playing Now?

[JimH]

Well, even with Auto Import off, I would guess if your NAS drives go to sleep (spin down) and MC tries to play the next track, which it tries to access before the current one finishes, then MC finds the file isn't available and removes it from Playing Now. MC then repeats the process for all remaining files in Playing Now, finds them all unavailable, and removes them from Playing Now.

I don't think that's the case.  We'd see a lot of problems if it were.

It's possible it could happen if the files are completely unavailable.

[RoderickGI]

It's possible it could happen if the files are completely unavailable.

Yes. If the NAS was powering down completely, or took a very long time to wake and spin up drives.

Although I just tested by adding files to Playing Now, then renaming a couple of files outside MC and starting playback. MC just skipped the renamed files. Maybe if the "Remove files from Playing Now after they are played" setting was checked... although if I turn that on I get the "Something went wrong with playback. File not found" message when MC gets to it.

I can't think of anything else that would result in what dichotomous1 has reported.

[RoderickGI]

I happened to be sitting at the comp when it just occurred.  Attached is the last 4 pages of the log. Full log avail if needed.

Those aren't any use. You need to post the full log file MC produces. The whole ZIP file. Set a maximum size of the log in MC if you need to, and if it is too big to post on the forum, upload it to Google Drive or similar and share a link to the file.

When you capture another event, provide the name of the last file played as well, so it can be quickly found in the log.

[dichotomous1]

I have the full log. It is too large to attach.    Google, no thank you.   
Both the full log from yesterday and the log from when it occurred last week are here:
https://www.dropbox.com/s/6b3r0jffp1tpgho/MCLog72220.txt?dl=0
https://www.dropbox.com/s/tixw07bdqwb5mfx/MCLog72920.txt?dl=0

As for the NAS spin-down theory or even renaming tracks, should that cause the entire list of Playing Nows to disappear ?   The only item that remains is the last song played. 
Also, the view changes.   The view was of a specific Zone.  When whatever it is occurs, playback stops (not mid track) and the view switches to Player, with the last song played being the only track listed.  Aside from when this hiccup, my Playing Now list for each zone has always remained saved and populated, even if I quit MC and reopen. This is also the case when MC has encountered a playback error.  The full list remains though playback has stopped.
But again, unless theres a technical issue, I play music via MC pretty much all day, every day and this hiccup does not occur every day.  I would assume if spin-down was the problem, that should occur several times daily.

 The timing of the hiccup is usually late afternoon. I've not noticed if there is a glaring consistency.  The behavior feels as if MC or one of the other parts of the system were updated mid playback.  I'm curious if this doesn't have something to do with my router or the zone.   I'm playing to a zone / Music Cast on a Yamaha Amp. This amp/zone is usually the lead in a Music Cast link with 3 to 4 amp/zone followers. 

[RoderickGI]

Ah. When a Zone becomes unavailable MC stops playback and switches to the default Player Zone.

Playing Now lists are Zone specific. So if MC switches Zones, it looks like Playing Now has emptied.

Is the Music Cast Zone still visible in MC when this happens?

Immediately after this happens, are you able to switch back to the Music Cast Zone? If so, is the Playing Now list there? I wouldn't expect it to be if the Zone vanished long enough for MC to notice and switch to the Player Zone.

I don't have a Yamaha Amp or use Music Cast, so I don't know exactly how it works or what Music Cast Link does, though I can guess. But it sounds like the Amp is doing something in the afternoons. Maybe checking for a firmware update? Or does someone try to take control of it with its Remote Control? Or does some other process on the network access the Amp around the time it happens?

See if you can reproduce the problem by playing a list of tracks to the Music Cast Zone and then powering down the Amp completely. Pull the plug. MC will "hang on" to the Zone for a time, but will eventually decide it has gone and switch to the Player Zone. I wouldn't expect it to show the last played track in the Player Zone though.


I had a quick look at one of the logs, but need more information to try to isolate the cause.
What is the name of the Music Cast Zone in MC that you play to?
What is the Zone ID and Zone Index of the Music Cast Zone? You can see those by hovering over the Zone in MC.
What was the last file played that remains in Playing Now when this happens in one of these logs, or a new log if you don't know for these two?

[dichotomous1]

Sorry for the delayed response, I could swear I had responded to this a couple of weeks ago. Since then I've been dealing with a little local wildfire issue which has now settled a bit.

When I looked into this last, my impression was there was something going on with my NAS, restarting or updating.  But something happened the other day that makes me think otherwise.

Last week, while frantically grabbing things and stuffing them in bags for evacuation, I disconnected my NAS.  (Later, I decided not to evacuate) About a week later I opened MC on my iMac, selected the zone for playback, "Media Room" (same zone that had last played to, and pretty much the zone I always play to.  The full list of tracks in Playing Now for that zone was still there, as it was last played. I double clicked the first listed track and I got an error message of unable to locate file.  Then I realized I hadn't reconnected the NAS. So this action would, in theory, be the same as the NAS updating, spinning down, or updating?  Either way, the NAS was offline.  but this time, the Playing Now list was all still intact. So whatever the issue is, its not caused by the NAS being offline.

I pretty much always play to the Music Cast zone named Media Room (currently device ID:10014 index 9) 

Please excuse if this is TMI, but in case something else is odd, I'm giving a every detail.

Is it possible this issue has something to do with my home router and dynamic DNS or the addresses being reassigned by the router?  Just a feeling, but honestly level technicality th is beyond my understanding. I have no idea when the addresses are reassigned nor what triggers it.  Nor the method the iOS Music Cast app uses to keep track of the zones if they use changing addresses, but its pretty much always worked flawlessly. What I do not know is how the audio files are handled via Music Cast. One item of note: If I select and play a DSD track via to a group of zones linked zones linked within the Music Cast app, playback is silent in the zones where the dedicated amp does not have the capacity to play DSD files. But when I play the same track via MC pointed at the primary zone (Media Room) linked as before to the group via the Music Cast iOS app, the audio plays in all zones.  I assume due to the PCM conversion being applied. So I expected the MC iMac server would be listed as the source, but the NAS is listed as the source.  Is that because the original file is stored there?  Ever since getting the Yamaha amps and utilizing a home LAN system, Audio Path lists MC isn't the audio engine.  Only when I listen to audio via my MacBook Pro and headphones. 

My usual procedure to play audio here at home is using the iOS Music Cast app, turn on the amps, select Media Room as the primary zone (amp), then link additional zones (amps) to play audio in sync around the house.  Each zone on the home has a dedicated Yamaha amp.  I use the Music Cast app to control the volume of the linked group. Track selection and playback via MC on my iMAC desktop and sometimes with the iOS remote app.  I'm unclear exactly as to what device is doing the actul "playing".  If I try to skip to the next track via the Music Cast app, playback stops.  So I stick to using the MC or remote iOS interface to play, skip tracks etc. MC on the iMac is set up as a server, files being converted to 24bit PCM with some DSP effects applied. When I play tracks with the MC app, to any of the available zones that appear in the side menu other than Player, the Spectrum Analyzer graphics on the MC skin view doappear (which is a bummer, I enjoy them) Audio Path states its not using the Driver Audiio engine.  One other slightly odd behavior is if I were to make any changes to the Network Server settings within MC, Playback stops about 10 seconds after I close the settings window.  Even if I make no changes and only view the settings, playback stops 10 seconds later.  Even if I Cancel out of the settings window, playback stoops 10 seconds later.  Basically overriding playback continuation as opposed to "changes are applied on restart" or "when playback is stopped"

Hopefully at least some this makes sense.  It's gotten late here and I've not slept well since the fires started, so I gotta wrap it up for now.

Thanks J

[RoderickGI]

I no longer use any Apple products, and I've never had a Yamaha AMP or used Music Cast. So I may be of limited help.

Using Dynamic DNS and having your external Public IP Address change will not be causing this issue.

If your router is changing the IP Address of devices on your LAN, this could be causing the problem. I recommend that you set up IP Address Reservation (also known as a Static Lease, but do not use Static IP Addresses) for all your network devices involved in music playback. A search of the forum will find lots of discussion on P Address Reservation.


I think this is the problem.

Ah. When a Zone becomes unavailable MC stops playback and switches to the default Player Zone.

Do a test to see if you can replicate the issue.

1. Start playback to your Music Cast Zone of a list of tracks in Playing Now.
2. We want it to just disappear from the network.
Either:
Power down the AMP ( primary zone (Media Room)) by pulling the power cord, as long as you think this is safe. Do not shut it down using normal means, as it might tell the network it is shutting down.
Or:
While MC is playing to the primary zone (Media Room), force a change of the IP Address of that AMP, perhaps by its own internal menu system.
3. Immediately check MC. The primary zone (Media Room) should have disappeared, and the Zone in MC should have changed to the default Player Zone if it exists. If the Player Zone doesn't exist, then I think some other Zone will be selected.

Did that reproduce the issue?
Is there only one track in Playing Now, and is it in the Player Zone?

[dichotomous1]

Since I dug into this last, the playlist contents clearing has occurred a few more times.  The thing is, I can't find anything consistently connected to the event.  It's happened at different times.  Always same result:  I leasve the computer with the current zone playing now list in view.  I notice there music isn't playing.  (so far I've not noticed playback stopping mud track, I think thats why I don't catch it the second it occurs) Return to the computer and the view is now on Player, with the last track played as the only track shown.  When I toggle to the zone I was playing (Media Room) the playing now list is empty, not even the last track played is shown.

What triggers the saving of Recent Playing Now lists located in the Smart Playlist tree? I noticed it doesn't consistently list what was perviously played the saved times are random.  Are they supposed to clear out daily?    I do recall one of the times this Playing Now list cleared out, I went to grab a copy of the track lust from the Recent Playing Now Smartlest and there was nothing saved.  I'm going to try to see if those get effected when this occurs next. 

I tried the cutting the power method and result was No Change.  The MC zone view stayed on Media Room and continued playing with seconds ticking off track time.

Couple of days ago, I came back to find an error message on the screen. A screen-shot of the error along with the logs for every time the event occurred since last post are here:  https://www.dropbox.com/sh/gbuw5x9i7kzl89v/AADm5N9BvmT5HLCU5VQ_UJEJa?dl=0

I have a new computer coming in a couple of days. I will see if this event occurs while running MC on it.  I've also not tried playing from my MacBook to see if this goes down.  Ill give them a try and let you know.

J

[RoderickGI]

I tried the cutting the power method and result was No Change.  The MC zone view stayed on Media Room and continued playing with seconds ticking off track time.

You might have had to wait for the next track change to see the issue. I should have thought of that.

But the error message you posted tells a story. It isn't that the Music Cast Zone has disappeared, it is that MC has lost control of the Music Cast DLNA Renderer. So when it tried to send the next track to the Renderer it couldn't. MC does monitor the Renderer to see if some other Controller has taken control, and I think it stops trying to control the Renderer if that happens.

Could some other device have connected to the Music Cast DLNA Renderer, and tried to send music to it, or maybe someone just viewed what was being played with another DLNA Controller, such as a phone App? Maybe someone occasionally checks what is playing, or how many tracks are left to play, late in the day, and that is causing the problem.

I haven't tried to test having another DLNA Controller taking over control to see what happens, but I have seen that message and it does disrupt playback. Also, any issue would only happen at track change, because with DLNA the full file is sent to the Renderer at the beginning, and the DLNA Controller would only notice it has lost control when it tries to send the next file.

[dichotomous1]

To clarify: the logs previously posted were for the playlist clearing out event.  The screenshot of the error message was the only time I have ever received any sort of error message relating to DLNA control. And after reading your response, I don't think it was related to the playlist clearing out event.  I'm sure you are correct about another iPhone throwing a wrench in the works.  Let's just say, on a Tech Savvy scale of 1-10, I give myself a 5, my iPhone toating other half is <0

The playback stopped and the Playing Now list cleared out again last evening, by the time I noticed, I was on to other things so I just closed the MC app.  When I reopened today I notice all the Recent Playing Now smart playlists that were there last night are gone. Is that set up to clear out on app close? Now I'm curious when exactly those clear out and if that is somehow related.   I'm also going to test today to see if it is triggered from me using the JRemote iOS app.  I've never altered or created a playlist with it, only skipped tracks within the Playing Now list I create on my desktop.

[RoderickGI]

I didn't check the logs again to see if a DLNA event happened in them. Understanding DLNA events from the logs is difficult, usually. I can't look now but might get a chance later.

However, the symptoms you described; Playing Now being cleared for the Zone you were playing to (Media Room in this case), and just one file showing in the default Player Zone, is consistent with a DLNA Controller taking control of the DLNA Renderer (Music Cast) and either viewing the play queue, or trying to play something using Music Cast directly, or doing something which would indicate that MC is no longer the DLNA Controller for the Music Cast DLNA Renderer Zone. MC does monitor to see if another Controller has taken control of a DLNA Renderer it is playing to, and will release control if that happens.

Once that happens, MC will likely switch to the default Player Zone on track change, and the track it was trying to send to the DLNA Renderer will be placed into the Player Zone Playing Now list. At least that is what I have observed previously.

One way you may be able to confirm this is if you know for sure that the single track in Playing Now was that last track actually played, or the next track to be played. In the scenario I described it would be the next track to be played, not the last track that was played. Perhaps you can try to confirm that when next it happens.

I don't use the JRemote App on iOS, but do use the JRemote2 App on Android. That has settings called "App follows server zones" and "Server follows app zones". If the MC Server is set to follow the App Zones, and someone opens the JRemote2 and changes the Zone then MC will change Zone. That doesn't cause the problem for me playing to a MC Renderer, but it might playig to Music Cast DLNA Renderer. Usually though, MC handles playing to two or more different Zones (audio devices) just fine. But if the Music Cast App was opened on iOS, that may not be the case.



Honestly, the  Recent Playing Now Smartlists are a bit of a mystery. MC manages them automatically of course, and it seems to create one when a change is about to be made to Playing Now, such as when a new track or tracks are added to an existing Playing Now list. I've also seen MC create one when I hit Stop, and when I hit Play after adding a bunch of tracks.

I used to think the list of Recent Playing Now's stayed for a day or so, but maybe that was only when I didn't restart MC. Just now restartnig MC cleared all  Recent Playing Now's. That behaviour is confirmed in the Wiki: https://wiki.jriver.com/index.php/How_Playing_Now_Works

Basically, it is a handy feature during a session, where tracks are being added to Playing Now, or perhaps a playing session involves selecting Album by Album to add to Playing Now. But it a little mysterious for me to rely upon.

That's why I tend to build Playlists rather than building a list in Playing Now, if I am concerned about keeping the list. Then I just play the Playlist, and add to it if I require. Playlists are always saved and retained, no matter what else I do in MC.

If I do spend a long time building a list in Playing Now I might save it as a Playlist every now and then, just in case I get called away, have a power failure, a PC lockup, or make some mistake that could mean I lose the work.

[dichotomous1]

So it just occurred and I was on the computer working in a different app.  No one else home that could have interfered. I wasn't using JRemote, only the Music Cast app was open on my phone and in another room.   This time playback stopped at the end of a track (title: Orchid), the Playing Now list for that zone cleared out except for not the last track played, but the one before it (title: Gentle Kind).   Player only shows Gentle Kind.  When I look at the Recently Played smartplaylist, the list is correct and has the last track played as Orchid.

So if something is awry with the handoff of the next track, this is where I get a bit confused with the MC interaction between Music Cast and the amp/zone. 

I don't understand why MC isn't considered the music engine in this scenario when it's MC that I am using to create the playlist and play the tracks, as well as apply DSP.  So if MC isn't the engine then the amp is, correct?  So is MC processing the audio file with DSP then handing off the complete track file to the amp or streaming it in real time as processed?  (I don't have any bit streaming options checked or on) Then it's some sort of hand off error between the amp and MC ?

I don't know if this is related, but I just realized that every time this has occurred, the linked group of zones I'm playing to has included a zone I don't always include.  Its a Yamaha amp connected to my network via Powerline Ethernet in my back yard. I only include it when I'm going to be outside. And I think this playback stopping has only occurred on those days. If I only play MC to the main zone in the link and let the Music Cast app do the link/sync of the additional zones. 

I have added the log for todays event to the dropbox.  https://www.dropbox.com/s/l0h53ldh0axv2yk/JRiver%20Log%202020-09-21%2014-30-00.zip?dl=0

Thanks. J
 

[RoderickGI]

The appearance of the second last track in the Player Zone is a little strange. But I have seen strange things happen like that when DLNA zones drop out during playback. I can't explain it, but know it happens. Well, I could guess as to what is happening, but I can't validate from afar. But it could be related to network issues, or DLNA connectivity from the Server to the Renderer.

Regarding the use of MC as the "Music Engine", do you mean that the MC Audio Path says "Not using the JRiver audio engine"?

When MC is playing to a non-DLNA output device, DSP is set up in "Options > Audio > Settings > DSP & output format". The DSP used will show in the MC Audio Path.
When MC is playing to a DLNA output device, DSP is set up in "Options > Media Network > Add or configure DLNA servers > {select the DLNA server} > Audio > Advanced > DSP Studio". Again, the DSP set up here will show in the MC Audio Path.

If you play to a DLNA device without setting up DSP in the DLNA server settings, then the MC Audio Path will say "Not using the JRiver audio engine". In that case, any DSP will be done on the AMP, not MC. In all cases, when playing to a DLNA device, MC just sends the whole file, whether it has added DSP or not. DLNA is a file based protocol, rather than a streaming protocol.

I have been assuming that you send music via this path:
MC -> Playback via a MC Zone -> DLNA Server -> Music Cast -> linked playback devices (AMPs) defined in Music Cast


Please clarify if you are actually doing this:
MC -> Playback via Linked Zones in MC -> Zone 1 in MC -> DLNA Server -> Music Cast instance for each MC Zone -> playback device (AMP) defined in Music Cast
                                                          \> Zone 2 in MC -> DLNA Server -> Music Cast instance for each MC Zone -> playback device (AMP) defined in Music Cast
                                                          \> Zone 3 in MC -> DLNA Server -> Music Cast instance for each MC Zone -> playback device (AMP) defined in Music Cast


Or if you are doing this when using the  Backyard AMP:
MC -> Playback via Linked Zones in MC -> Main Zone in MC -> DLNA Server -> Music Cast instance for Main linked Zones -> Main AMP 1 defined in Music Cast
                                                                                                                                                                                \> Main AMP 2 defined in Music Cast
                                                                                                                                                                                \> Main AMP 3 etc. defined in Music Cast
                                                          \> Backyard Zone in MC > DLNA Server -> Music Cast instance for Backyard Zone -> Backyard AMP defined in Music Cast


Or maybe you are always linking the Backyard AMP in Music Cast:
MC -> Playback via a MC Zone -> DLNA Server -> Music Cast linked Zones -> Main linked playback devices (AMPs) defined in Music Cast -> Main AMP 1
                                                                                                                                                                                                      \> Main AMP 2
                                                                                                                                                                                                      \> Main AMP 2 etc.
                                                                                                             \> Backyard AMP defined in Music Cast


Basically, are you linking AMPs via linked Zones in MC, or via Linked devices in Music Cast, or via a combination of both?

If you are using a mixture of Linked Zones in MC and Linked device in Music Cast to support the Backyard AMP, it would be good if you could test only using Music Cast to play to all Zones, and not use Linked Zones in MC.


As you are using a Powerline device for the Backyard AMP, is it a recent model? Reliable? Good throughput and no dropouts? Early models weren't very good. It could be that the Powerline can't support the network stability required for DLNA playback. It would be good if you could confirm that the issue only happens when the Backyard AMP is in use.

[dichotomous1]

It just occurred while I was adding songs to the Playing Now list, so I got to see more of what is going on. (Note: I'm typing this out before reading your last response so that I can get it down quickly)

 A new track started playing from the Playing Now list I had created yesterday and had been listening to for the past hour or so. I added tracks to that list prior to playing and Reshuffled the Remaining Tracks.  I was adding more tracks to the zone Playing Now list, then the spot in the file list view I was choosing from (The Rolling Stones) disappeared and the view changed back to the top of the file list alphabetically at A.  I looked at the tree and the zone I was playing (Media Room) was no longer listed (but my other zones were still listed but the track was still playing(note: almost off of the other zones including the one connected via power ethernet are linked to the Media Room zone via the Music Cast app so shouldn't they all have disappeared?).  The zone appeared for a second then disappeared again.  Play was still uninterrupted.  And now as I type, the track that has been playing ended and playback of the list stopped.  The entire playing now list is gone from that zone.  Looking at the Recent Playing Now's smartest, there were 6 tracks I added before the library list disappeared and they are not included in the Recent Playing Now's list. 

[RoderickGI]

The track kept playing because the full file had already been sent to the Renderer, Music Cast.

If the Media Room Zone in MC disappeared and the other Zones remained, MC can see them as DLNA Renderers regardless of the Music Cast status, and shows them as Dynamic Zones. Unless you have them set up as individual Zones in MC.

So Music Cast is dropping off the MC Dynamic Zone list, but the individual AMPs are not. The problem could be Music Cast, or MC's tracking and management of Dynamic Zones like Music Cast, which may not (probably isn't) fully DLNA compatible. I have certainly had some trouble with DLNA Renderer that don't appear in MC as Dynamic Zones when they should, or appear inconsistently, and unreliably.

When Music Cast is dropped as a Dynamic Zone, the Playing Now list disappears with it. When Music Cast comes back its Playing Now list will be empty. Playing Now's are attached to the Zone they are playing to, so if the Zone disappears MC has no place to store the list.

Anyway, read my previous post and see if you can clarify your setup further. Although You have a bit already by saying the all of the other zones are linked to the Media Room zone via the Music Cast app.

[dichotomous1]

That makes sense that Music Cast is suspect.   I have no idea exactly how any of that functions in the background. 

You mentioned how I set up the zones.  I never did any setup of the zones in MC.  I just enabled DLNA and they all appeared.  I got a new Mac a couple of days ago and am trying to set up MC 27 on it and same thing, all my amps show up as zones. 
If I link them in MC, will that sync playback of all the zones the same as Music Cast?  If so, I'll just do it that way, leaving Music Cast out of it and see if that solved the issue.

[RoderickGI]

Okay. The Zones are appearing in MC because all the AMPs are advertising themselves as DLNA Renderers. That is fine. They are what JRiver calls Dynamic Zones, because they come and go as MC sees them. You don't have to use them.

You could try linking those Zones in MC and playing to any linked Zone should play to all linked Zones. Or you could set up a Zone Group and add each Zone to that Group. In each case, MC should play to all visible Zones (AMPs, acting as DLNA Renderers). I don't have your setup so can't say how well that would work. A couple of things to note though.

• Playback may not be synchronised, or may not stay synchronised. MC has some functionality around synchronising playback on Zones (Options > Features > Precision Zone Sync), but it isn't very robust. I understand it works best with independent DLNA Renderers, such as in your situation, so it may work well enough, if synchronised playback is important to you. I know at least one other user uses Music Cast to ensure synchronised playback. In another case a user is playing to BubbleUPnP which is then casting to Chromecast devices, which also does a reasonable job at synchronisation I understand, but of course has quality limitations.
• I'm not sure exactly what happens if Dynamic Zones that are linked or in a Group disappear and then reappear. That seems to be what is happening in Music Cast in your situation, and Music Cast doesn't handle it well. MC may handle it better.

So basically, you could try it. There should be no harm to your MC setup, and you could just unlink or ungroup the Zones if it doesnt' work.

[dichotomous1]

Got it.   Music Cast did an update last night and now doesn't recognize my server.  So I'll reach out to them and cover this topic as well.
Thanks for the help.