Maybe... maybe not.
I've had a couple balanced systems, and in two completely different homes... one old, one brandy new.
going balanced in the old home didn't help. Going that way in the new one was better, yet not dead silent.
Another way to quickly narrow down the problem to either a poorly operating ckt, item, or appliance causing the issue, is to simply begin by turning on the system and then opening up the house' breaker box, and start flipping off breakers.... or turn them all off save for that which drives the system, and then one by one, turning them back on, and checking the system for the buzz as you go along. Naturally, if all else is off except for the power ckt (driving the rig) and you have the buzz already, it's likley in the way the home is wired to ground.
Depending on local NEC codes, the neutral (white wire) and the common, or ground, the green one, are bonded (tied) together in both the braker box and definitely outside at the service itself.
Most often, as I said, the dish or cable box is the culprit. sometimes the phone system, such as Verizon FIOS (fiber optic system), even those uninterupted power supplies for computers are providing the nastyness. I found that last one out the hard way.
Battery chargers, devices which need recharging periodically, they too can induce noise back into the homes electrical system.... some more so than others.
To totally isoalate ones ssytem, both the neutral and ground must also be independant or dedicated.... not just the hot wire.
A difference of potential in the grounds can also provide a ground loop.
turn off everything and then start energizing things one by one... and see.... if there's no change, lift the ground on the cable or dish rig at the service pole.
BTW... I put cheater plugs on all the appliances in my home as I was able... so now only the dryer, hot water heater, and oven are wired directly.
remewmber if it's the cable box, there are filters which can fix things.
