Audio/Video out of sync for Linux guest (since 5.2.20)

[sunrider]

Host: Ubuntu 16.04 Guest: Ubuntu 16.04

Playing video (e.g. in FF Browser on YouTube) always has audio out of sync (audio lagging behind). Problem is reproducible.

The problem is NOT present for Windows 10 guests on same host system.

The problem was NOT present on VBox 5.2.18 and has been introduced with VBox 5.2.20.

[sunrider]

Linux guest log file

[pw2]

I see this significant audio-out-of-sync problem too as introduced with version 5.2.20 -- log files have been uploaded -- it affects youtube and offline video file playback within an Ubuntu 16.04 guest -- version 5.2.18 does not have this audio sync problem -- the problem has been pushed forward into Virtualbox 6 beta

[pw2]

@pentagonik @michaln

I have an update to the problem above:

The audio-out-of-sync problem (Ubuntu host with Ubuntu guest) is no longer present as of version 6.0.4 (Thanks!!) (the problem does remain in the 5.2 branch (as of 5.2.26)) -- can the audio code fix in VirtualBox 6 be applied to VirtualBox 5.2 ?

Regarding 5.2.26: something must have changed in Ubuntu or the Linux kernel as the problem no longer exists as a ~1/2 second audio/video mismatch, it now does keep mostly in sync but is very scratchy as it skips audio bits in order to catch up -- VirtualBox on Ubuntu with Ubuntu guest works perfectly if version 6.0.4 is used -- versions 5.2.20 up to at least 5.2.26 have scratchy sound (or out of sync sound with older Ubuntu code)

Thanks for fixing this in version 6 as it does give me a good path forward