Will:

The moving around of the 950 is pretty easy to do; you could move it sideways to another shelf, or to the top of your TV to see if anything changes. The hum has to be coming from _somewhere_,it is just a matter of eliminating as many possibilities as you can by unplugging things, seeing if it makes a difference, then proceeding to another input. If the hum bothers you enough, it's really worth trying to find the source. I have a persistent but very low level hum in my system I've been trying to track down for weeks, months. I know it's coming from the crossover and power amp section, not from anything upstream. I've taken the crossover apart, measured and looked at the power supply rails on an ocilloscope - nothing. I've built a DC regulated power supply for the filiments of the vacuum tubes in the single ended triode amp - gets rid of a slight buzz I had in the tweeter horns but no effect on the basic low level hum. I've encased some elements of the filters in the electronic crossover with layers of "co-netic" magnetic shielding foil - again, helps lower the hum, but it's still there to some extent. This kind of stuff can drive a person nuts, so I know how you feel!