1524753 - Audio stuttering on Twitch since 64.0.2

Status: UNCONFIRMED

(Core :: Audio/Video: Playback, defect, P3)

Description

[MikeZ]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0

Steps to reproduce:

Windows 10 X64 1804 / Firefox 64.0.2 - 65.0 / Geforce GTX 1060 with uptodate drivers

• Launch a Twitch stream in a tab
• (optional) Let the tab/window unfocused for a while

Actual results:

Either one of those :

• Frozen video with ok sound
• Sound out of sync with the video (but video ot frozen)
• Short sound infinite loop on top of the regular stream sound.

Expected results:

Well none of those problems should have happened of course.

I must mention i tried :

• updating my NVIDIA drivers (not realy sound related but who knows)
• a fresh profile
• reducing the stream quality

Nothing worked.

The interesting fact is : i noticed there was a fix about stuttering in 64.0.2 and this is exactly the version i got when those problems started.

I will try with HW acceleration disabled, of course, and come back with the results.

Comment 1

[Gingerbread Man]

(In reply to MikeZ from comment #0)

The interesting fact is : i noticed there was a fix about stuttering in 64.0.2 and this is exactly the version i got when those problems started.

It would be very helpful if you could find the exact regression range.
https://mozilla.github.io/mozregression/quickstart.html

The fix you mentioned is bug 1513511.

Comment 2

[MikeZ]

I am trying mozregression right now, but it could take a while.

Its already taking some time to reproduce the problem in a single build because i have to let the stream tab unfocused for a while and there are too many builds to tests, and mozregression is progression backwards (65 to 64) instead of upwards...

If you could give me some hints to reduce the testings, like buildid or dates it would be quite useful.

I am certain this wasnt happening in release 64.0 (i watch streams everyday i would have noticed).

Comment 3

[Nils Ohlmeier [:drno]]

If I'm not mistaken readable streams landed in 65 see https://bugzilla.mozilla.org/show_bug.cgi?id=1389628
This was a feature requested by Twitch, because their low latency playback mode depends on availability of readable streams. I'm wondering if these are side effects of Firefox users now automatically using the low latency player.

Comment 4

[Nils Ohlmeier [:drno]]

I have reached out to Twitch to learn if there is a way to find out which player is in use, or if there is a way to force using one or the other player.

Comment 5

[Nils Ohlmeier [:drno]]

Wondering if bug 1525507 might be related.

Comment 6

[Michael Froman [:mjf]]

Any change since Bug 1525507 landed in Nightly?

Comment 7

[MikeZ]

(In reply to Michael Froman [:mjf] from comment #6)

Any change since Bug 1525507 landed in Nightly?

Testing last nightly right now (fresh profile ofc).

I give it a few days, and different streams for testing, because it may depends on the low latency feature and we have no way to know if the streamer activated the feature.

Comment 8

[Jean-Yves Avenard [:jya]]

(In reply to Michael Froman [:mjf] from comment #6)

Any change since Bug 1525507 landed in Nightly?

This is extremely unlikely to have any impact, that bug is about allowing twitch vp9 test stream to work. Those aren't seen in production. Twitch uses h264

Comment 9

[MikeZ]

This is strange. I tried on nightly 67.0a1 since my last message, and i didnt have any problem.

Now it seems that the problem disappeared from 65.0.1 Release too. I cant say when because i retried on 65.0.1 two days ago just to make sure its not a change on Twitch side.

I didnt changed anything in Firefox nor on my computer.

Maybe Twitch changed something on their end...

Comment 10

[btbn]

The described issues (Video freezing, audio still going. Short audio loop, ...) are happening since a while for me again.
Currently I'm on 68 aurora, but it might have already been happening on 67 aurora.

Comment 11

[mattwilliamwillis]

Can replicate this issue in 69.0.3 (Windows 10.0.4393, enterprise edition). Am behind a proxy that is explicitly configured within Firefox. Can provide further details if required.

Comment 12

[torokati44]

I'm also affected on Firefox 81.0.1 (64-bit), Fedora 32.