video will not sync up to audio in final cut pro
I have 4 black magic video assists which I record my tutorials on. I have 4 dslrs attached to the back magics.
I use a mic and we pick up sound on the cameras too.
We have recorded 100s of videos without hitch until last week, I bought a new version of the video assist to replace a faulty one. However, we can see and play the video and hear the audio but this one just won't sync up to the other three in Final Cut Pro.
Is there anything we can try? I have contacted Black Magic but they recon it's a FC issue.
Thanks in adavnce
iMac 21.5″, macOS 11.5