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Audio and video go out of sync with HDMI capture

Posted: 22 Aug 2023 14:00
by Jason_25
I am using this command to capture audio and video:

Code: Select all

cvlc v4l2:///dev/video0 --v4l2-chroma=MJPG --input-slave=alsa://hw:2,0 --alsa-audio-device=default --aout=alsa
Eventually the audio and video lose synchronization with each other and are even off by several seconds sometimes. I have tried setting caches to zero already for instance with no change. I have since reverted to a default VLC configuration.

What could I do to fix this?

Re: Audio and video go out of sync with HDMI capture

Posted: 22 Aug 2023 17:58
by RĂ©mi Denis-Courmont
VLC is just passing the timestamp from V4L2, and deducting the reported ALSA latency from current time.

If it drifts, then one of your device driver is probably reporting corrupt timings.

Re: Audio and video go out of sync with HDMI capture

Posted: 23 Aug 2023 00:25
by Jason_25
Thanks for your time. It seems that the Fire Stick, connected by HDMI, needed to be rebooted. It was basically the last thing I tried before giving up.