Occasional audio dropouts whe watching 25fps media

It is very rare that I come across this frame rate but every time I do I get occasional one second audio drop-outs where the video continues normally. This only happens when I have the Pi adjust the display refresh rate to match video. So yes not doing that does fix it but I prefer it for the 99.999% of other media I have that works fine with 23.976 or 29.97 frame rates. Only the one rarest frame rate has this issue.

Debug log http://pastebin.com/Hj6ZEk9h
Please not I did ssh into the system and was watching the debug log with tail -f when some drop-outs happened and nothing showed in the log what so ever. It had not moved before or after.

My setup is a Raspberry Pi 2 > Onkyo TX-SR608 Receiver > Samsung f5500 series TV

I finally got the right wording in a Google search and found a answer for the same description of my problem. I just need to add this “hdmi_clock_change_limit=20” and it should fix my problem. I’m testing it now.

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So that did fix the drop out problem but caused a worse one by breaking CEC. Without it I have a working CEC setup between all three devices.
But when I add that fix after turning off the TV and Receiver I lose CEC controls my TV loses the connection to the Receiver which then causes blocks the Pi from getting the remote presses.

The only fix is to have the TV scan the CEC network then reset the sound output to Receiver. Then the Pi gets the remote presses. But it stops again when I shutdown.

I have removed the clock limit for now since it is a rare problem and the remote is vital but would like to figure out how to have everything work at the same time.

My setup is still Pi > Receiver > TV

I’m pretty sure hdmi_clock_change_limit is not related to your CEC failure.
Another options is to remove hdmi_clock_change_limit and disable omxplayer in video/acceleration settings. That should also avoid the dropouts.

I’ll try that when I get a chance. I couldn’t figure it out either why that would affect it but it only started happening after that one change and then stopped when I reverted it.

I also have small aufiojitters or dropouts (using passthrough) when the pi2 is set to adjust the framerate of my tv.
I need to set that option though to not get any stutter in the video.
Isn’t this option supposed to be the best option available if the tv supports it?

It worked perfectly with raspbmc but with osmc I get those small dropouts.
They don’t seem to depend on the framerate of the movie though as I get them with 24, 29,9 and 25 Hz SD or HD material.

Does hdmi_clock_change_limit fix it? This defaulted to a lower number on older firmware. I’m planning on reducing it again, but haven’t decided what value to limit it to. It would be useful if users can report the highest value that avoids the audio dropouts.

Note the dropouts depend on the TV/receiver. Some are happy with arbitrarily high values, but others are more fussy. The Onkyo 609 is very fussy, but strangely the Onkyo 606 is not.

I will try it and report the results.
I have a LG 42lm640s tv that gets the hdmi signal and passes it to my pioneer vsx920 receiver via optical out.

Just to follow this up:
I can get away with a value of 30. The dropouts seem to be gone and cec is working on my side.

Thanks for the advice!

Now I watched a whole movie. About 2/3 into it, the dropouts came back. Will try to set it even lower.

Have you tried setting config_hdmi_boost=4 (or higher) in your config.txt ? (Via the OSMC settings addon)

No, haven’t tried that, but can do it if you think it will help. So there seem to be some differences in the hdmi signal between pi 1 and 2 …