Tim,

Don't know if this will help, but before I ran my equipment off the dedicated AC outlets I had installed, I got popping from certain appliances/light fixtures that were on the same circuit my 950 was plugged into.

Any intermittent appliance such as refrigerator, steam iron, electric blanket, space heater, etc., and especially when the adjacent room's flourescent light fixtyre was turned off, made varying degrees of popping sounds.

Dedicated 20 amp outlets and a Tripplite line conditioner eliminated this problem for good.