now the metal pignose knob. has some play ( maybe 1/2 inc to 1/4") in it before you hear/feel a click as it wold turn on. im not sure if that was done in shipping or not. i have done nothing yet, besides try different battery's.
Mine does too, it's worn from being turned on & off a lot - because its been used. I think this is a weakness in these amps.
On a pignose, if you pull the guitar lead out, the amp turns off, even if the amp nob is still turned on. It is designed like that to save flattening the batteries.
Trust this is of some use.