First of all, is your amp or preamp tubed? If so, change the tubes around until you discover which tube is causing the problem.
If no tubes, is there any new component in your system?
It may be causing a ground loop hum. Try floating the ground on varying pieces of equipment (caution: do not float all grounds at once!), starting with the new component (if indeed there is a new component).
I assume that if you're not using tubes, that you've made some change in equipment, and that change has a different ground potential then your previous setup.
Last, but not least, disconnect any and all cable tv or satellite wires from touching your system in anyway. This also could cause a problem.
Hopefully one of these three ideas will help you out.
It would be easier if we knew more about your system.
Tubes? New equipment? etc.
Cheers,
John
If no tubes, is there any new component in your system?
It may be causing a ground loop hum. Try floating the ground on varying pieces of equipment (caution: do not float all grounds at once!), starting with the new component (if indeed there is a new component).
I assume that if you're not using tubes, that you've made some change in equipment, and that change has a different ground potential then your previous setup.
Last, but not least, disconnect any and all cable tv or satellite wires from touching your system in anyway. This also could cause a problem.
Hopefully one of these three ideas will help you out.
It would be easier if we knew more about your system.
Tubes? New equipment? etc.
Cheers,
John