Instrument tracks won't play when reopening sessions

I've had this issue regularly since installing PT11 upon its release and just keep working around it. Here's the poop: I have an Instrument track and on it I place an Avid stock VI or a 3rd party plug-in. Record/edit a bunch of stuff, save and close the session. Reopen the session (can be immediately or another day, doesn't matter) and 9 times out of 10, one or more of the VI tracks won't play back.



They aren't inactive, the inserts open as expected, but the MIDI info on the track is greyed out as if the track was inactive or didn't have an instrument inserted. Removing the VI and reinserting it doesn't bring the MIDI info "back to life". The only solution I've found is to create a new Instrument track, copy the MIDI stuff to in and reinsert the VI. PITA....



Makes me wary of doing too much in the way of composing in PT. Any one else seeing this or know of a solution?



Thanks!