This thing is awesome! It's running my sub and 2 tower speakers - a 5" 6" and tweeter in each. the towers are rated for 100 watt. I'm no audio file but everything sounds crisp. the blue light is a little bright for my taste so I need to figure a remedy for that but that's my only complaint.
mitch_dropI'm not Entune, but I did just plug a sub into mine.
It isn't clear to me what you mean by output being on with the amp off, but I can say that I have a really bad hum with mine, even when the amp is off. As-is, it is unlistenable.
j.a.lI have an active sub, that turns on automatically with a signal input and turns off, when there is no signal after a few minutes. The amp is always sending a sub signal, thus my sub is always on, even when I have the amp off, when I don't want my stereo blaring... Turn the amp on, the sub output works normally, attenuating volume as you would expect. Turn it off, the sub output is still putting out a bass output, albeit soft in volume, it's still putting out something, which it shouldn't.
mitch_dropThanks for the clarification, I understand what you mean now. I think we are talking about the same symptom, although it seems like you don't have the hum to the degree I do.
Mine is active, too (Audioengine S8). Doesn't matter if the amp is on or not, volume knob makes no difference. Unplug the amp, it goes away. Position relative to other objects consuming power makes no difference. The amp and speakers are on a UPS; I tried moving the amp first to a different UPS and then also to wall-mains on a different circuit, no difference. The amp is connected to my machine via SPDIF; there is no electrical path from the computer to the amp, so the only paths involved are UPS -> amp, R/L to passive speakers, sub out to the S8. The speakers have no hum, the sub hum is awful.
Pretty sure the sub out is defective - bad ground? Or at least, I can't guess what else it could be. I'm going to wait a bit for other replies here and elsewhere, because I'm not that experienced with audio and may be overlooking something, but may end up cracking the case and seeing if there's an obvious bad join or something I can fix myself. I don't expect SMSL to be responsive.