Salue Jean
I will try tomorrow as it is already late here in \.ch
Dunno if using a real video clip in Fusion should show better performance in edit tab than just using a compound clip....but gonna try your Fusion settings...
Still don't know how Fusion caching should influence playback performance in edit tab...
inside Fusion it is just using the 1080 GPU and plays in realtime...
Also don't believe it has to do with APFS filesystem as the same behaviour is seen on my Linux box...
And I never had issues with 1080p60 recording om macOS with my Intensity Pro 4k card.
I still have a ticket open with BMD for this issue (besides the other Linux background merge crash ticket
BMD support answers really fast...but mostly they turn it into their way of saying "we don't support this hardware, setup, blah whatever"
Feels like chatting with Amazon support (o;