i just have a few questions about my new mac pro when i start up my tower by pressing the power button there seems to be a strange electrical noise? now i dont know if this is normal or not but it is a similar sound like when you have a loose connection in a mains plug a sort of "szzzzzz" sound only for a second or two. also i have a bluetooth keyboard and mighty mouse and if my mouse is more than a meter away from the tower the on screen pointer seems to stutter when it is moved if i move it closer to the tower its fine? is this normal or do you think there is a problem with the bluetooth signal or device? or some sort of interference?