Hey guys,
So I had to record a few presentations this week.
My setup is a Lenovo Legion 5 (Ryzen 5800H, RTX 3060, 16 GB), I captured the camera and the presenters laptop through Elgato capture cards. I was editing live (switching between screens) but also had Multicorder running to have a backup so I can fix any mistakes in post.
I was recording in 20 Mbps (12 for the multicorders), vMix version is 25.0.0.24, I used Hardware Encoder and H264 Baseline

I've used this setup dozens of times before (sometimes with 3 separate capture cards, using 3 multicorders), never had any problems, but this time the recording became mostly unusable.
Did not see any problems in the preview window, but the bitrate of the recording fluctuates. There are minutes when it works, then it just falls apart, sometimes for a few seconds, sometimes for 5-8 minutes.
And it's not just a bit blurry, it usually falls apart hard, like in the picture I have attached. So from 20 000 to 200 kb/s



Any idea what causes this?