Thanks for helping, Alain!
No, I haven't tried it without midi hooked up, but I also had that thought and will try it for a bit.
The glide mode is set at the standard Fixed Rate, so... I think I'll hook up an extra midi connection either by doubling or the thru-jack and monitor it, to see if there's any message being sent to the Rev2 that could cause this behaviour. Strange thing is the Glide button is still lit, and when I press it twice, deactivate and activate it, it starts working again, until next time it disappears.