Forgot to mention, the MP3 player in the AUX-in was the first thing I tried when I couldn't get any sound from my guitar.
Pedal calibration had no effect, and yes the power brick puts out 9V AC 2000 mA. (it's not the original though, I didn't get one.)
I think I'll pass on the reflashing thing. It's got v3.01 now, and does that monkey thing even run on Win8.1 64 bit?
Most likely I'll return it tomorrow, it seems broken to me.
Thanks for all the helpful tips though.
Cheers!