I sent in a help ticket, but wanted to now if anyone else has seen this.
I turned on my PRO3, and I hear the usual start up chatter, and then only the pitch wheel and mod wheel lights are on.
No other lights, screen blank, no sound... (attached a photo)
I just used it last night, so I'm really mystified.
The only difference I can think of is that it's about 5 degrees colder in my home studio this morning.
Edit: I was able to get it working again, and sharing this in case it helps anyone in the future. First I noted that the Pro3 was sending midi to my Mac. I decided to wiggle each knob and found that the octave knob for OSC2 was somehow between "clicks". Once I touched it the whole synth woke up and is fine. Whew!