it did it again when I fired it up today, even though it was on channel two, had to reboot then it was fine, and just for the record it has froze up a few times, mostly full controls and no sound but a couple total freezes, but a reboot has brought her back to life everytime so far. But to be fair my Prophet 12 and my supernova have issues too, I had to send my Kronos back for a warranty exchange a while ago so this is just the nature of the beast.