Audio Sync

[BLAlley]

I've been using Avidemux for a while now, starting in Windows and continuing after switching to Linux (Unbuntu 24.04 based Zorin OS). It always worked well, until this week it decided to not play audio in sync with the video on any file I drop into it.
I verified the integrity of the files by playing them in VLC, Shot Cut, Totem, and Plex Media Server clients and the web interface. All play them perfectly.

I'd appreciate any insights into why it's suddenly not working since it's become unusable. It's version 2.8.1. Thanks.

[eumagga0x2a]

It's version 2.8.1.

You should be much better off using the latest available pre-2.8.2 appImage or (better) building from git master yourself. The 2.8.1 release is really ancient.

It always worked well, until this week it decided to not play audio in sync with the video on any file I drop into it.

The first thing to check should be an accelerated video display in Avidemux (i.e. NOT the "Qt" one which performs all the computationally expensive color conversion and scaling work on the CPU). The second one is either using a HW decoder or enabling libavcodec decoder multi-threading. Please inspect corresponding settings in Avidemux Preferences.

If your PC has a NVIDIA graphics card using the proprietary (closed-source) driver, VDPAU video display + VDPAU hw video decoder (libavcodec multi-threading disabled) should give the best results. If your PC has Intel graphics, LibVA (VA-API) video display + LibVA (VA-API) hw video decoder should be optimal for playback (not for re-encoding due to slow data transfer from VA-API video "surfaces" to main memory, which makes libavcodec decoder multi-threading often beneficial).

If all your videos you currently try to play are HDR videos, the HDR to SDR conversion in Avidemux uses a lot of CPU power and may be too slow for real-time playback.

If you already use the optimal video display and video decoder combination in Avidemux, a software (kernel, mesa etc.) update may have broken hw acceleration (not necessarily for other players).