Ooops - the e-mail notification of this post's appearance on the forum was put into my Spam Suspects folder, and I got to it after I'd posted my question on the diagnosis of corruption.

It's clear that it's an empirical diagnosis - a file which causes Juke Box to hang is (by definition) corrupt.

There is an alternative explanation - that these are files which reveal a fault in BIAB's Juke Box feature.

The origins of many of these files go back ten years or so, and they've been used mostly for practice and for the production of lead sheets. Our recent introduction of RealTracks to our systems has led us to upgrade some of the instruments from MIDI to RealTracks, but I think we'll still have the old MIDI tracks in backup folders that we could go back to, and avoid the need to rewrite them all.

Thanks, Mac, for all your work in investigating this for us.