Bumping this because I forgot my pass word. Actually, Update 3...alas, the new amp in the EVSxa100 did NOT fix the problem. The shop called EV and they said that we should check the placement of the amp and another item in the guts because some have been incorrectly put too close together resulting in a hum in some speakers. I brought the EV home because I need it for 2 Christmas Parties this weekend. I set it up to tweak it today and it really sounded great despite the low hum...kinda like the hiss...you don't even notice it. However, It's getting returned for a new one next week...I mean, it is a known flaw, so why should I have to accept a sub standard speaker right out of the box...I know EV will fix it, but I don't want a fixed one, I payed for a new one...anyhow, just wanted to let you know, the hum doesn't effect the speakers at all...they really sounded great today...Cheers Brian