Topic: Stuttering after channel surfing (Read 6624 times)

raym · « **on:** November 14, 2011, 03:35:51 pm »

Hi Yaobing, you may recall me describing this issue a few months back. It's still a problem in v17 and may be related to some of the other jerky playback threads.

In my case, tv playback is very smooth and stable UNTIL I start channel surfing. After a few channel changes, I get bad audio stuttering. Pausing a second or hitting right arrow always fixes it. What both these actions do is increase the TS buffer slightly so I'm confident the problem is related to this. Perhaps the channel changes sacrifice some buffer size for improved channel change performance? A little more tuning may be needed.

RO in use here although I've experimented with other codecs- same problem. Also using wasapi es.

Thanks.

Yaobing · « **Reply #1 on:** November 14, 2011, 04:20:27 pm »

Can you provide a log? Or remind me of a previous log provided. I am trying to see if this is related to the problem when background recording starts while watching live.

raym · « **Reply #2 on:** November 14, 2011, 09:40:14 pm »

Quote from: Yaobing on November 14, 2011, 04:20:27 pm

Can you provide a log? Or remind me of a previous log provided. I am trying to see if this is related to the problem when background recording starts while watching live.

Yeah no probs. I can't find the last log I sent you. I'll get another one together for you.

Thanks.

Yaobing · « **Reply #3 on:** November 17, 2011, 03:05:55 pm »

I just remembered something. What audio mode do you use (ASIO, WASAPI. etc.). When using some modes (not all modes), audio would loop on the last available bits if new data is not available (can happen when switching channel, because it takes some time for the tuner to switch to new channel). I made an attempt to fix the issue, but am not sure how well that fix was. Can you try different audio modes and see if there is a pattern?

greg.smalter · « **Reply #4 on:** December 26, 2011, 11:45:43 pm »

I agree that channel changing sometimes creates problems, and even when it doesn't it is rather slow. I'm familiar with the bit looping problem you are talking about because it happens if you have a bad antenna signal, but the problem I get when changing channels is different.

What often happens to me right now is I'll hit ch+, the sound and video will stop (fine) and there will be a wait, then the sound from the channel I am changing FROM will play again for a second and then it will actually switch the channel. This is for a single press of the button. The problems get worse if you overwhelm MC with more channel changes than it can keep up with.

gvanbrunt · « **Reply #5 on:** January 06, 2012, 10:40:43 pm »

I have a similar problem. When I switch channels (nearly 100% of the time) I get no sound and my receiver channel input lights (shows which speakers are active) flash on and off repeatedly. I also have sync issues with the audio not matching the video and the occasional hiccup in the audio.

As requested I tried it with lots of Output Modes and Output Settings. Nothing seems to work. For the record I've tried Direct Sound, WASAPI, WASAPI -Event Style and various settings for flushing buffers.

I then tried changing the DSP settings and found something interesting. I had it set to 5.1 with no up or down mixing and to output to Dolby Digital. As soon as I shut off the Dolby Digital setting things changed. Now on channel changes I get looping audio that doesn't stop unless I play with time shifting. I can sometimes get audio back that way. Audio sync issues appear to have gone away however and I don't get any hiccups. My CPU is nowhere near maxed out so I don't think this is related to that.

One other thing I notice: if I pause I lose picture (don't know if that is normal). Then when I hit play sound resumes but picture does not. Hitting stop again to end time shifting usually gets me sound and picture back.

I'm currently using HDMI for output, but I'll switch over to Optical tomorrow and report the results. That may be part of the issue.

gvanbrunt · « **Reply #6 on:** January 07, 2012, 03:00:28 pm »

OK more updates on this. Tried Optical cable instead of HDMI and it made no difference. So that eliminates a sound driver since one is NVIDIA and the Other is Realtek (I think). I also played with turning bitstreaming off and on and that made no difference. In all cases CPU was around 25% only.

I also noticed that the video is actually BEHIND the audio even though it seems the audio portion is the one struggling.

So to recap, anytime I change channel on the set top box the audio gets messed up in MC. The exact symptoms vary a bit depending on settings, but the result is the same - looping or no audio. There is also the audio sync issue and the hiccuping which seems to be tied to DSP encoding to Dolby Digital. Finally if I Pause or timeshift video seems to disappear. Pehaps timeshifing is the key to it all? Is there anything I can test?

gvanbrunt · « **Reply #7 on:** January 07, 2012, 04:39:44 pm »

Not sure if it helps, but here is log of the following:

Opened MC.
It defaults to Theater View so I hit esc twice
Already on TV Page in Standard View so I double click on SerialDigital Hauupauge to view tv
I use my DishNetwork control to change channels.
Channel changes and audio drops out.
Hit the Stop button.
Viewed Log and saved to disk.

gvanbrunt · « **Reply #8 on:** January 07, 2012, 05:07:47 pm »

Another log of related weirdness. This time I start TV. Hit pause. The video goes black. After about 2 seconds the audio continues again for a few seconds. After a few more seconds the receiver lights start blinking showing it is looping. Monitor blinks cause resolution is changing or something. MC crashes.

I tried a few times and many times it crashes in either ntdll or out_main with an access violation. When it does not I can hit stop and it cancels time shifting. Sometimes audio comes back, sometimes it does not.

gvanbrunt · « **Reply #9 on:** January 07, 2012, 05:27:13 pm »

Definitely something going on with timeshifing. If play with it. I can sometimes get sound back and when it does it is in sync.

gvanbrunt · « **Reply #10 on:** February 23, 2012, 08:18:31 pm »

Bump

Sorry to be pain, but I am not able to get this working. I'm happy to provide time, logs, debugging, whatever to help fix this.

Yaobing · « **Reply #11 on:** February 24, 2012, 09:03:49 am »

Quote from: gvanbrunt on February 23, 2012, 08:18:31 pm

Bump

Sorry to be pain, but I am not able to get this working. I'm happy to provide time, logs, debugging, whatever to help fix this.

Do you know what audio formats are used in your satellite channels? I am guessing different channels may have different audio format.

gvanbrunt · « **Reply #12 on:** February 24, 2012, 05:51:32 pm »

You mean 5.1 or stereo? If so SD are in stereo and HD are in 5.1. I have the problem no matter which one it is using. It's Dish Network btw...

If you mean codecs, I think the Colossus only outputs AAC.

Yaobing · « **Reply #13 on:** February 24, 2012, 06:11:40 pm »

I meant codec, such as AC3 vs. MPEG-2.

I knew the device only output AAC, but wondered whether it had any by-pass mode, in particular for the input that you selected. At least I know AC3 is by passed. If channel switching caused audio to switch between AC3 and AAC, what happens?

gvanbrunt · « **Reply #14 on:** February 27, 2012, 05:14:57 pm »

I'll do some more playing around with this. I'm gong to use component in from the receiver and a few other things.

Do you know of any way I can find out what audio format the receiver is sending to the colossus? I know theoretically what it should be sending, but assuming that is probably not a good idea.

NickF · « **Reply #15 on:** March 05, 2012, 09:03:13 am »

I am a newcomer to TV on MC17 and have just got my DVB-S card working with MC. I started out with RO HQ and Hardware Acceleration set as this works well with BluRay. With TV, this causes regular lockups and even complete system crashes. I discovered that unchecking Hardware Acceleration drastically improved this. However, there was still some stuttering during normal play.

Changing channels caused several of the syptoms mentioned in this thread. Changing to RO Standard has helped reduce the video stalls and stutters on channel change. The serious issue remaining is the time shift between audio and video, audio being up to a second ahead of video.

It shouldn't be necessary to make these changes of settings when the system runs OK with movies. It wouldn't be so bad if the changes could be made automatically but that isn't possible within TheaterView. It isn't even possible to have different settings for each Zone.

So these seem to be serious bugs which need to be resolved.

Playing TV and changing channels are two absolute fundamentals of a TV app. These need to be top of the list of priorities.

I'm going to have to change back to Windows Media Center for now until these problems are fixed.

Nick.

gvanbrunt · « **Reply #16 on:** March 05, 2012, 04:37:44 pm »

On thing that has made troubleshooting difficult is the inability to change codec's etc for live TV. I think it would narrow down a lot of issues. Is this in the roadmap for the near future?

Yaobing · « **Reply #17 on:** March 05, 2012, 07:36:29 pm »

Quote from: gvanbrunt on March 05, 2012, 04:37:44 pm

On thing that has made troubleshooting difficult is the inability to change codec's etc for live TV. I think it would narrow down a lot of issues. Is this in the roadmap for the near future?

Yes.

gvanbrunt · « **Reply #18 on:** March 05, 2012, 07:55:46 pm »

That is excellent!

raym · « **Reply #19 on:** March 05, 2012, 08:31:02 pm »

Quote from: gvanbrunt on March 05, 2012, 04:37:44 pm

On thing that has made troubleshooting difficult is the inability to change codec's etc for live TV.

What do you mean? I'm using a custom codec config for Live TV without issue. I based it on ROHQ where I have configured JTV to use AC3Filter and EVR. This works fine for me and overcomes an issue I have with DVB-T audio drop-outs when using straight RO (even though this is supposed to be a non-issue).

gvanbrunt · « **Reply #20 on:** March 05, 2012, 08:44:54 pm »

If you are talking about playing back recordings, that I believe you can. However for live TV you cannot change the codecs or renderes used as far as I know.

Yaobing · « **Reply #21 on:** March 06, 2012, 12:25:53 am »

I think you two have a little different definition of "live TV". One is live TV played in time-shifting, the other is live TV played in non-time-shifting. Non-time-shifting graph does not follow RO rules right now.

NickF · « **Reply #22 on:** March 06, 2012, 05:13:45 am »

Quote from: Yaobing on March 06, 2012, 12:25:53 am

I think you two have a little different definition of "live TV". One is live TV played in time-shifting, the other is live TV played in non-time-shifting. Non-time-shifting graph does not follow RO rules right now.

Can you clarify what you mean by this please, Yaobing? Presumably non-time-shifted Live TV is using the RO Standard or RO HQ settings. I know that changing between them makes a difference.

Nick.

Sandy B Ridge · « **Reply #23 on:** March 06, 2012, 06:34:35 am »

Quote from: Yaobing on March 06, 2012, 12:25:53 am

I think you two have a little different definition of "live TV". One is live TV played in time-shifting, the other is live TV played in non-time-shifting. Non-time-shifting graph does not follow RO rules right now.

Quote from: NickF on March 06, 2012, 05:13:45 am

Can you clarify what you mean by this please, Yaobing? Presumably non-time-shifted Live TV is using the RO Standard or RO HQ settings. I know that changing between them makes a difference.

Nick.

I think the nontimeshift TV engine dates from before RO and has a manually built graph. The time shift one has two graphs, one for the tuning and recording and one for playback. I'm not sure if the playback one at the time of live TV has the same RO properties as a 'cold' one for playback of a recording.

SBR

NickF · « **Reply #24 on:** March 06, 2012, 08:55:43 am »

Quote from: Sandy B Ridge on March 06, 2012, 06:34:35 am

I think the nontimeshift TV engine dates from before RO and has a manually built graph. The time shift one has two graphs, one for the tuning and recording and one for playback. I'm not sure if the playback one at the time of live TV has the same RO properties as a 'cold' one for playback of a recording.

Thanks. So the question is, for non-time-shift Live TV, does the manually built graph use the same RO and ROHQ components with the same settings? If I select ROHQ versus RO Standard, will this impact on Live TV? If I choose ROHQ and make changes to settings in madVR, will Live TV use these settings?

Nick.

Yaobing · « **Reply #25 on:** March 06, 2012, 09:17:21 am »

Quote from: NickF on March 06, 2012, 08:55:43 am

Thanks. So the question is, for non-time-shift Live TV, does the manually built graph use the same RO and ROHQ components with the same settings? If I select ROHQ versus RO Standard, will this impact on Live TV? If I choose ROHQ and make changes to settings in madVR, will Live TV use these settings?

Nick.

Quote from: Yaobing on March 06, 2012, 12:25:53 am

Non-time-shifting graph does not follow RO rules right now.

When you play digital TV live, MC automatically use time-shifting and all RO or ROHQ settings are honored. Non-time-shifting does not follow RO rules, but you will only be affected if you manually cancel time-shifting.

Analog devices are not started in time-shifting mode that is where we have problem.

NickF · « **Reply #26 on:** March 06, 2012, 10:15:30 am »

Quote from: Yaobing on March 06, 2012, 09:17:21 am

When you play digital TV live, MC automatically use time-shifting and all RO or ROHQ settings are honored. Non-time-shifting does not follow RO rules, but you will only be affected if you manually cancel time-shifting.

Many thanks, Yaobing. So MC delays playback of Live TV slightly to work in time-shifting mode. So, in this case, should VideoClock work? If so, that would be excellent news. Can the delay be adjusted?

Nick.

gvanbrunt · « **Reply #27 on:** April 12, 2012, 07:54:38 pm »

I figured something out about this and my Colossus card:

If I change channels it will start stuttering etc every single time. I can also fix it by pressing the right arrow button on the remote. That works every time.

An ugly work around, but at least it is working. Won't help me with recordings though etc. Any idea why this is happening?

Yaobing · « **Reply #28 on:** September 23, 2014, 05:24:28 pm »

Does everyone who had this problem still have it?

If you still have this problem, I would like to know whether you use STB or other tuners.

I have tried a few things in the last couple of years. I hope you guys have not all given up on me

Anyway if what I have tried have done any good, it most likely will be with direct tuners such as ATSC or DVB-T tuners, and not STB with a capture device (such as Colossus).

gvanbrunt · « **Reply #29 on:** September 24, 2014, 12:18:00 pm »

I'll try to hook it up and see what happens. Haven't tried in years. I'm pretty swamped (doing renovations) but I can probably do some basic tests.

For me I could reproduce by manually changing channel on STB. I was not using any other tuners or capture cards.

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Author Topic: Stuttering after channel surfing (Read 6624 times)