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[InflatableMouse]

As mentioned in this thread here I'm experiencing sound that is ahead of the movie.

I have videoclock enabled and I'm using ROHQ.

Soundcard is an Asus Essence ST with H6 expansion. I am using the latest Uni drivers.

In the ASIO control panel I have a latency setting. I'm not sure when or why I should change that (I don't know why that is there, basically). It ranges from 1ms to 80ms but as I need to set A/V Sync in MC to 300ms, that setting doesn't quite cut it.

For now, I've left the ASIO CP to its default to 10ms and I've configured A/V Sync to 300ms for 24Hz and 50/60/120Hz.

Questions:
1. What exactly is that CP Latency setting for? Does it introduce an artificial latency and if so, should I just set it to 1 to let MC deal with A/V sync?
2. MC only seems to have settings for 24, 50, 60 and 120Hz displays. Does this mean A/V sync is not used when I play a movie in 23.976 or 29.97 or does both settings include all display modes?

3. Why am I having this issue? How come sound is actually ahead of the movie? I never had to play with A/V sync settings before and if there ever was something, sound was lagging and not ahead. Can I fix this or is A/V Sync the way to go?

Thanks guys!

[dean70]

Id say it is the length of the buffer in ms. I tried with 6ms, which worked fine with audio and 24hz 1080p, but with 1080i, 29.97 i  t   s o  r  t   of  h  a  d   t his stutter effect. 10ms worked fine.

[mojave]

This article at SoundonSound explains the ASIO buffers and their usage. I believe JRiver already knows the buffer size and is supposed to compensate to sync the video with the audio. However, as you said the audio latency isn't the issue since the video lags the audio. I usually keep my ASIO buffer fairly small. I recently had an issue where it was too small and changes from audio tracks in 96/88.2 kHz to tracks in 48/44.1 KHz were causing an error. Increasing the ASIO buffer size solved the issue.

I'm first going to assume that the audio and video are leaving JRiver in sync. Do you have anything else in the signal chain that is cause latency in the video? If you have a receiver and have the distance settings set on the receiver it might cause an issue. Also, and video processing done by the receiver or display device could cause an issue. If overscan isn't turned off in the display device then it will be resizing and could cause latency.

If the audio and video aren't leaving JRiver in sync, it could be caused by too high of setting in madVR. Have you played with any of the setting such as queue size, backbuffers, or flushing? I don't know much about them, but maybe they are delaying the video slightly. Do you have all processing turned off in your video card drivers? Is there any resizing going on in the drivers or in madVR?

[InflatableMouse]

This article at SoundonSound explains the ASIO buffers and their usage. I believe JRiver already knows the buffer size and is supposed to compensate to sync the video with the audio. However, as you said the audio latency isn't the issue since the video lags the audio. I usually keep my ASIO buffer fairly small. I recently had an issue where it was too small and changes from audio tracks in 96/88.2 kHz to tracks in 48/44.1 KHz were causing an error. Increasing the ASIO buffer size solved the issue.

Thanks Mojave. I'll read that article later (almost time for bed here and I got an early morning ).

To be clear, the buffer is the slider in the ASIO Settings right? Do you use large hardware buffers or should I disable that?

I'm first going to assume that the audio and video are leaving JRiver in sync. Do you have anything else in the signal chain that is cause latency in the video? If you have a receiver and have the distance settings set on the receiver it might cause an issue. Also, and video processing done by the receiver or display device could cause an issue. If overscan isn't turned off in the display device then it will be resizing and could cause latency.

Audio leaves analog out to the receiver. The receiver has room correction enabled and I'm no longer using Pure Direct Mode. Video is passthrough, it leaves as 1080p from the PC over HDMI to the receiver which does nothing. TV does nothing but display the image (no overscan, its 1:1).

If the audio and video aren't leaving JRiver in sync, it could be caused by too high of setting in madVR. Have you played with any of the setting such as queue size, backbuffers, or flushing? I don't know much about them, but maybe they are delaying the video slightly. Do you have all processing turned off in your video card drivers? Is there any resizing going on in the drivers or in madVR?

That's interesting. I didn't think of video processing on the PC to possibly cause a delay. I just did some quick tests as my own PC has an Essence as well and I'm experiencing the same thing there (PS, I had this on Windows 7 too but I saw no reason to use ASIO). Ro Std doesn't make a difference and my own PC has a GTX580 that can take any sane Madvr setting without blinking.

I've not done anything with the buffers and flushing; I have no idea what it does and how that works.

I'm surprised no one else has this, there are several people with an Essence using ASIO ... I'm trying to think what's different in my setup that could cause this, but I come out blank

[mojave]

To be clear, the buffer is the slider in the ASIO Settings right? Do you use large hardware buffers or should I disable that?

Here is a quote from TheLion:

There are 4 relevant buffer settings/levels:
1) ASIO hardware buffer (to be set in the ASIO device driver - this depends on the hardware)
2) "ASIO buffering" within JRiver (output mode settings). Even when I select "use large hardware buffers" it doesn't change the buffer set in 1) (as confirmed by enabling diagnostics) I have this at 1sec
3) Pre-buffering under Audio -> Settings, default = 6sec, should this be increased when running complex DSPs (like 16+ channel convolution)?
4) "Play files from memory" option. I am not sure how this works in case of Blu-Ray playback, but I guess using it doesn't make much sense (in general, and for Blu-Ray playback in particular)

Please advice "best practice" buffer settings for 2), 3) and 4) given Blu-Ray playback. Then I will test some TrueHD tracks for any remaining anomalies. Thank you!

Here is Matt's reply:

#3 and #4 don't matter for video.  And rarely matter for audio.

#1 and #2 are important. 

I think it's fine to max #1 (normally like 2048 or 4096 samples).  For #2, you want the smallest value that still gives playback without hiccups.  For me this is 10ms at home.  Since you use convolution, you might need a larger value.

#2 is what I think you are referring to and #1 is what is referred to in the SoundonSound article. Checking "use large hardware buffers" only works with some hardware (not mine) and increases the buffers referred to in #1.

I hope this helps.

I'm surprised no one else has this, there are several people with an Essence using ASIO ... I'm trying to think what's different in my setup that could cause this, but I come out blank

Maybe you listen too fast!  You could try a different video driver from Nvidia. You could check your drivers to makes sure that scaling is set to No Scaling under Adjust Desktop size and position. Even though I didn't need scaling, this was causing an issue for me once. At the time it didn't seem like the setting should make any difference, but it did. I still don't understand why.

Does you receiver have a lip sync setting? Could this have gotten adjusted?

Just for testing, you could connect straight to the TV with the HDMI from your video card. This would at least eliminate the receiver as the culprit.

[InflatableMouse]

Here is a quote from TheLion:
Here is Matt's reply:
#2 is what I think you are referring to and #1 is what is referred to in the SoundonSound article. Checking "use large hardware buffers" only works with some hardware (not mine) and increases the buffers referred to in #1.

Right. I don't think I have all of them, but I'll check and play around. Thanks for that.

I hope this helps.
Maybe you listen too fast!  You could try a different video driver from Nvidia. You could check your drivers to makes sure that scaling is set to No Scaling under Adjust Desktop size and position. Even though I didn't need scaling, this was causing an issue for me once. At the time it didn't seem like the setting should make any difference, but it did. I still don't understand why.

Does you receiver have a lip sync setting? Could this have gotten adjusted?

Just for testing, you could connect straight to the TV with the HDMI from your video card. This would at least eliminate the receiver as the culprit.

I'll have another look at the drivers, I'm using the latest for Win8 and never touched its settings for video stuff. Never hurts to check though.

The receiver does have audio delay, but only up to 200ms and I don't think it works on the analog inputs, only on the digital ones. Also if the receiver was the problem it would happen regardless of ASIO or Wasapi and Wasapi is spot on. Nevertheless, I can easily plug the hdmi from the receiver to the tv so I'll try that.

Thanks again! Bedtime for me now .

[InflatableMouse]

I went back to Windows 7, no problem with this anymore.