HGS-15 Velodyne Sub

I have just recently purchased the Velodyne HGS-15 sub. The sound is great. However I am having two problems and would like imput from other owners of this sub or anyone else.


1. I do hear a hum (possibly mechical due to the servo/accelerometer) - I believe a mechanical type hum (hum is still heard when no interconnects are connected to sub) (Also and sub has no ground connected to it). During normal scenes in a movie I do not hear this hum since the other sound is masking it. However during some quite scenes, say some scenes in Matrix or Pleasenville (a very quite movie), I do notice this hum (I sit approximately 15 feet away form the sub. I only put the volume up to approximately point two (approx. 20%). Is this normal for this sub?


2. I have set the sub to turn on automatically whenever it gets a signal. However the sub is also turning on sometimes whenever I turn my hallway light switch on, or furnice turns on (both on seperate circuts than the sub or audio equipment). I tried removing all grounds which did not work. I have a DC-1 as my preamp pluged into a Monster HTS 1000 surge surpressor. I belive that when the light switch/furnice is turned on the switch may spark (sometimes) and cause the subwofer to see a signal (somehow?)and turn on automatically.


Any suggestion to the above problem would be greatly appreicated.

I already exchanged the sub for another HGS-15 and spent several hours tring different things - but still the same problem.