All of a sudden, Video/Audio are out of sync

[johnnyerato]

Hi, I have been using OBS for over a year to record audio and video simultaneously using 1 audio source and 1 video source. All of a sudden, yesterday, the audio and video are totally out of sync. Any idea how this happened. I recorded 6 videos on Monday alone perfectly, but yesterday I tried to and they are both way off. Any assistance would be appreciated. Thanks in advance.

 

[Lawrence_SoCal]

real-time video encoding is VERY computationally demanding. and if your system is busy, it is easy for audio to be processed faster.
I recommend monitoring hardware resource (CPU, GPU, RAM, Disk I/O, etc) utilization [for ex. using Task manager’s Performance tab and/or Resource Monitor] to see if your system is being maxed out with your settings https://obsproject.com/wiki/General-Performance-and-Encoding-Issues and https://obsproject.com/wiki/GPU-overload-issues

Also, there have been OS and OBS updates over last year, so lots of possibilities a driver change, or you updated other s/w and that is causing a different workload profile than before. For example, OBS v28 has some new options, some of which could be CPU demanding. Or you might have other software (unrelated to OBS) running in the background causing contention.. or new/updated security software... the list of potential issues is long.
I recommend following pinned post (linked in my .sig) regarding posting an OBS log from a recording/streaming session (probably worth starting with automated Analyzer, address issues noted in it first, re-run a streaming/recording session (at least 30 seconds), then post log here

 

[johnnyerato]

Thank you. I guess the reason this took me by surprise is because I have recorded hundreds of videos over the last year including 6 on Monday without even one having a sync issue. And then on Tuesday, the two I tried to record both were horribly out of sync.

 

[Lawrence_SoCal]

Unless you monitor and know what was running in the background, hard to say. It would be easy for an app/process to have been in the background, not causing any issues, then an update/change happens (possibly outside that one app/process) causing the app/process to behave differently (work harder in this case)... but that is only one of many possiblities