ibanez amp

[Gunn_Slinger]

Hi guys
I have an Ibanez tone blaster 100h amp head. It played good when I bought for a week.
Now, when I play the low E string using the neck pickup ( on any of my guitars ) its a half step flat. The rest of the notes are ok. Im stumped. If I back off the volume on the guitar , the note is ok. No computer chips in this amp that I know off. Overload on the input voltage???.....no clue
Thanks
Clay

[stokes]

Sounds like a power supply problem.

[Gunn_Slinger]

thanks
how would the power supply do that?

[Gunn_Slinger]

does anyone know where i can get a schemetic of this ibanez tb 100h amp head?
thanks
Clay