Do you have cable television in your home? If you have a single family home and can find where the cable is connected to the outside of your house, check how they have grounded it. If the cable has a ground wire, usually green, going to a conduit pipe..there is a chance that the cable feed has placed a DC voltage on your system. The easiest way to check is to disconnect the cable altogether..meaning at the outside of your house disconnect the 75 ohm coax and take off the green ground wire from the conduit...then listen..
if this is not the case or you do this and nothing happen, ..then you have other concerns..but if it does help...then get a qualified electrician to ground that damn cable feed to earth and make sure your home AC is properly grounded.. try to find an electrician that knows hi-fi.
P.S. You have way too good of a system, set up well for it not to sound pretty damn good.
To be clear..I should say that, in most cases, what the cable feed is doing is placing a DC voltage on your homes AC ground.
if this is not the case or you do this and nothing happen, ..then you have other concerns..but if it does help...then get a qualified electrician to ground that damn cable feed to earth and make sure your home AC is properly grounded.. try to find an electrician that knows hi-fi.
P.S. You have way too good of a system, set up well for it not to sound pretty damn good.
To be clear..I should say that, in most cases, what the cable feed is doing is placing a DC voltage on your homes AC ground.