1801222 - Bluetooth audio video latency on Android worse than Chrome browsers

Status: RESOLVED FIXED

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

Description

[Jamie Kitson]

User Agent: Mozilla/5.0 (Android 12; Mobile; rv:108.0) Gecko/108.0 Firefox/108.0
Firefox for Android

Steps to reproduce:

Watch a video in Firefox for Android using Bluetooth earbuds, eg, on BBC News or YouTube. Note that this doesn't seem to be YouTube specific.

Actual results:

Noticeable audio lag on Firefox that is not present in chrome browsers or the YouTube app.

Expected results:

Video and audio are synced.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Audio/Video: Playback' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Jim Mathies [:jimm]]

Paul, any thoughts?

Comment 3

[Paul Adenot (:padenot)]

Jamie, would you mind giving us the kind of Android device you're using? Are you effectively using Android 12 as noted in your message? I'm not seeing this locally on my devices.

Comment 4

[Jamie Kitson]

My device is an up to date Microsoft Surface Duo with Android 12L. I've recorded a demo here: https://www.youtube.com/watch?v=sw9GpYwhSkM
I'm happy to provide the original if it would help. On the other hand I'm happy for you to close this bug if you think it's something specific with my setup or just not an issue. Thanks.

Comment 5

[Paul Adenot (:padenot)]

Yeah, it's indeed not synced properly on this device. I'll look into it, thanks for filing!

Comment 6

[Paul Adenot (:padenot)]

Jamie, can I ask you one more thing, would you mind installing Firefox for Android Nightly, that installs fine alongside a regular Firefox, and create a pref called media.cubeb.backend, that you set to the string aaudio, restart Firefox and try again with a bluetooth device?

Attached is a screencast that shows the whole process.

Comment 7

[Paul Adenot (:padenot)]

Attachment: Setting a pref to switch audio backend on Firefox Nightly

Comment 8

[Jamie Kitson]

Nightly with that setting appears to still show the lag.

Comment 9

[Paul Adenot (:padenot)]

Interesting, it's better for me on a Sony Xperia 5 II + airpods, I'll continue digging.

Comment 10

[Paul Adenot (:padenot)]

Not that it was terribly bad before, but it's perceptually worse on videos specially made for A/V sync check.

Comment 11

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jimm, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 12

[Paul Adenot (:padenot)]

I've got us a fix in https://github.com/mozilla/cubeb/pull/735, I'll import it soon in Firefox.

With this, A/V sync is perfect in Firefox regardless of the audio output device I'm using (wired/speaker/bluetooth).

Comment 13

[Paul Adenot (:padenot)]

Fixed by enabling the fixed AAudio backend, in bug 1809185. Reporter, can you please test with an up-to-date Firefox Nightly, available in the Play Store? This version is going to be released as stable on the 14th of February.

Comment 14

[Jamie Kitson]

Yes it appears fixed in Nightly. Thanks!