PJB BP800 Head problem

[RoyA]

I recently came into getting a BP-800 head and I have a noticeable treble hiss. The hiss is more pronounced if I turn up the gain, anywhere from zero! It is also loud when I turn my bass EQ knob to the treble side past the midpoint. I've tried different cables and nothing seems to alleviate the hiss. Has anyone else run into this problem with their BP-800 head?

 

[agedhorse]

Is the noise present without anything plugged into the input jack on the amp?

 

[Arpi]

Hallo did you get rid of the hiss problem, I got the same hiss problem now,

Greets Arpi