Affected versions

• 67.0b12

Affected platforms

• macOS 10.13 ;

Steps to reproduce

1. Launch Firefox, access any video on youtube and click play;
2. Increase the PC load (open up multiple tabs in Chrome);
3. Pay attention to the sound while PC is on high load.

Expected result

• audio is properly played back;

Actual result

• sound was intermittently disappearing/appearing;

Regression range

• will provide one asap;

Additional notes

• see also bug 1524193, as per the initially reported issue the sound was not being played back for 1-2 seconds while PC on high loads; what stands out is that there are no PC hangs while the issue manifests;
• confirmed the issue on 2 devices(so far): Imac14.1(8gb ram);
• the opened tabs did not have any audio/video components that would interfere with Firefox;
• the nature of the issue is intermittent; the scenario was opening ~70 tabs in Chrome(issue appeared), closed them, open up ~90 tabs(issue did not appear).

Paul, any thought on who should look at this?

Me, but I'd like a regression range. I don't think we've changed anything that could have caused this.

Cristi, let me know if/when you can have a regression range, this is pretty surprising.

Will get to it by next week, if it's not to late.

We are about 2 weeks away from release and this affects beta. Cristi, could you please provide the regression range this week?
Paul, are you able to reproduce?

Spent several extra hours to familiarize myself with the macOS. Opposed to my main OS, Apple devices handle the hangs-freezes a bit better.

What stood out was that it seemed to have the same behavior as the initial bug as the threshold for when the available memory is filled and the video starts lagging as well seems to be close to it.

Another thing worth mentioning is that today I managed to check with the current nightly build and 66.0.2; so in case it's a regression for fact it's not introduced in the current cycle.

Unassigned P2, we don't have a regression range but it seems that 66 was also affected. Marking as wontfix for 67 since we only have a beta left.

I think this is expected for now? What makes us think it's a bug?

As per the discussion with :padenot on Slack, will close this issue.

To summarize:

• due to the fact that the PC is on high load the fact that the sound had issues similar to the initial bug would be expected;
• with other browsers; while they behave a bit different, they all end up exhibiting the same symptoms (audio/video freezes).

Closing this issue for now, and will keep an eye out for the future.