Hi, I use a LOT my many registrations banks in my T2 and I did with my PSR 3000...and I get that message often, but I ignore it, usually by pressing "song",like if I was to choose a midi file to play (aldo, I do not use them), and that, makes the message go away.
I wish Yamaha do something about it, is not a real problem, but is very annoying!!, mainly when you are playing life before audience.