I have had the this noise when i was using speakers with a high sensitivity rating like 90 db and above. They seem to show more electronic noise.
If your pre-amp has an adjustable gain like a surround pre-amp or a receiver try setting it to a lower gain.
Good luck !!
If your pre-amp has an adjustable gain like a surround pre-amp or a receiver try setting it to a lower gain.
Good luck !!