Odd crackling with PXA-H701 / RUX-C701

Odd crackling with PXA-H701 / RUX-C701 Has anyone experienced this before? Just bought a 701 combo. When I turn the rotary encoder on the RUX-C701 in volume mode there is a little crackle of distortion as it passes over each "notch" in volume value. I imagine the source of this crackling can only be from either RUX or PXA units, hence I assume I have a "bad" one? This occurs in any input mode, i.e. analog or digital. Also, when I turn the unit on (even in digital input or analog input mode), at low low volumes (incl. 0) there is a faint mix of "swirling" tones, swinging up and down in pitch. I am going to go through several trial measures (moving power/ground wires further away from unit, trying different amps, cables, etc.) in order to deduce the source of the problem. I would appreciate input that anyone has on this. System consists of the following, all installed over the past week: -Analog rca input from head unit -Digital input from Kenwood DVD changer -very short (6") rcas from PXA outputs to McIntosh 431 (4x100W), no EQ installed (except basic factory plug-in with adjustment options at 40Hz and 150Hz) Speaker wires and speakers have not changed from previous system, where there was no trace of these issues. thx Maxdestination moon

does it do it both with the car on and off?