[marty martin]

Yes bustromo, we have noticed this as well in our college. We have 30 eMacs and at least 2 or 3 of them will experience this exact same problem every day, mostly with just a small MIDI session 3 or 4 tracks (no virtual instruments). It appears to be completely random and not specific to any one particular computer, sometimes it will lock up the machine and require a restart but mostly like you say, we just save, quit and reopen. We assumed it was a bug in 6.4 but we'd love to hear any solutions especially from Digi (don't say the problem is 10.3.5 cos I'm sure it happened in 10.3.4 as well)