Hi! Today I tried to update my DT25 head (again) and failed the first time. I've read all the posts here and nothing seemed to work. I gave up and 3 hours later I gave it another try: powered the amp, started L6 Mokey and catchau! Communications restored, firmware updated. Maybe this error just needs you to turn the amp off for a while and then give it another try. Could it be a buffer/memory issue?