For a while now, whenever I export an AAF with separate media, when I then mount the exported media to check it is all ok, there are lots of segments offline. It is usually title media and precomputes media that are missing. I have to labouriously sort about 20 -30 of them for every export I do. This is over multiple Z400s/420/440 pcs and earlier versions of MC and exported to a QNAP network server.
The red segments on the timeline are offline after an AAF export.
