I had my Digitone on for several hours. I was playing various factory presets, then left it alone for a while.
I heard a click, looked around and saw it was off. I tried the power switch, nothing.
I checked the power brick, it was supply 12V according to my multimeter. I left it a while and tried plugging it again hours later. Still dead.
I contacted Amazon, they said to return it for a full refund.