Thanks. I'm still in doubt as to whether I should keep it. I've tried it again a couple of times, and each time I had to have 5-10 tries before it gets past the startup window. Today I had to resort to firmware reinstall, then another 4-5 tries until it started. Before firmware reinstall I had tried at least 10 times without success. I had removed EVERYTHING from the power circuit, including the Mac power supply. Then, after an hour of programming the thing I turned it off just now. I sneakily turned it on again, had to try 4 times before it started. Faulty unit, methinks. If this is something that's considered normal I will return it, as I don't want to risk that kind of situation on a gig. Weird really, as my other Line6 gear has worked straight out of the box, my 1st generation Pod is still soldiering on after 17 years, as is my Pod XT Live after 9 years. My GR30s work well too, but the Helix has me worried.