hartke ha3500 problem.

[Landshark]

Ok i´ve been having this problem for quite some time, and since I retired this amp I havent given it a thought, but now I moved it to another rehersal place and its getting played again.
I have the compressor switch of but the light keeps turning yellow, even at low volumes, running flat and regardless which pre-section I use (tube/solidstate) This is the earlier model.
Theres something going on there...

 

[figuredbass]

Make sure the compressor knob is turned fully counter-clockwise, sufficiently to hear/feel it click off. If the control is turned all the way "down" but not actually clicked off the compressor is still operating.

Even with the compressor turned fully off, the light may still turn yellow if you are sending a very hot signal into the amp, especially a hot signal into the passive input. But as long the switch is off there will be no compression in your sound even if the light is flickering.