When you guys have your sub set to auto and the receiver is off, is the led light still green? I have an Onkyo TX-SR505 and when I turn it off the led light for the sub-100 stays green and I'm sure it's not on the on position. When I switch it to off the led light turns off.

No it goes off when I turn my receiver off or when it is idle for to long.

When the switch is set to the middle option(auto), it turns on when it detects a signal, and the opposite should be true when you turn off your receiver. That's how it works for me anyways.

:( maybe i got a lemon

i unplugged the subwoofer cable while the receiver was off and put the selector on auto. when i plugged the cable back on the light turned green even though the receiver was off. you think maybe there's something wrong with the receiver instead?

it's weird because in the little pamphlet that came with the sub, it says that it should be red if it's in the off or standby, maybe the pamphlet is outdated?

also, if it's green does that mean it's constantly sucking power? or does it not matter since it's not being used?

Did your sub-100 ship with the knobs on the amp for the gain and freq?
I just got my sub-120 and the knobs are missing.

Sorry for the off topic question.

My SUB-100 shipped with the knobs attached. You might want to contact Dayton or Parts Express(assuming you purchased it there) about the missing knobs.

On the original topic, the power LED on the sub turns off completely when my receiver is off. No red light for me. I would imagine the red light goes on when not in use when the switch is flipped to the "off" position.

do you have the sub plugged up with just a rca cable or did you use a y cable?

The LED is only green on my SUB 100,when set to auto it lights up when I turn on my receiver and off after 15min.
I read that in standby it uses 15w.

I used a mono RCA cable connected to the right red input on the sub. Works like a charm.