Thank you for the response Anna,
I did already know to convert H.264, but when I am using them it is normally just to switch out a title card at the end of a TVC so transcoding to Prores is a waste of time for a 5 min job. the syncing with H.264 isn’t that much of an issue, but it is still out if I play the TVC back in FCP.
Generally I am working with Prores 422(HQ) or HDV 720 encoded files.
The audio files are mostly .WAV, or sometimes AIF
Thanks.