So here's what I've got: I bought this surround unit, and I haven't been able to figure out how to set get sound from my subwoofer. I have been over the manual about 30 times, and i have called Pioneer CS reps to see if they could figure it out. Nothing still. Here is what i have done so far: First, I verified that the subwoofer cable and subwoofer were still good, and I did this by testing it with another surround unit that i had lying around. After i verified that those were still good, I tried to run the MCACC auto configuration tool. Everything was good till it tried to do the sub channel. No sound. not even a faint vibration. Then i scoured the manual, trying to see if it had something to do with a subwoofer mute or perhaps the LFE setting. I could not find anything on a channel mute, and the LFE setting was a dead end (so far). This is the point in time that I called Pioneer Tech services. The guy went through all of the things I had already done, and then we checked the MCACC settings. I made sure that the speakers were set on small, all the way around, and set the subwoofer on plus. Still nothing. Then we tried adjusting the output level of the sub, and still got nothing. Finally, he had me pull the sub cable, and plug it into one of the front speaker pre-out jacks. Then I started getting a bit of sound from the sub. The conclusion that the CS rep came up with was that the Sub Pre-out jack is bad, and that I need to send the unit in for repair. I have not given up yet, but i need some help. I have been wracking by brain for any possible issue that i may have overlooked, and I'm coming up with nothing. The unit is out of warranty, so this is my final stand before I send it in. Thank you in advance.