toggle the hold switch about 5 times
then hold the play and menu button untill the appel logo appears(make sure that when you toggle the hold switch you finish with it not holding)
Yeh, a soft reset like tippyninja said might do it. If not then look in your manual or online for how to do a hard reset. You will lose all the stuff you had on it, but at least it will be up and running.
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Current guns
Blue DM5
Blue to Black Lotus Cocker(in the process of building)
Black 2k2 Cocker E2'd and MQ'd
Blue Spyder e99