I got an x-sub the other day, hooked it up through the LFE input and everything worked great. I was watching a movie tonight, and the sub just quit playing in the middle of it. I checked the settings on my receiver (Marantz 4001) and everything seemed ok. I played some rap music, thinking that should trigger its auto-on, but it didn't. I tried hooking it up through the line level and speaker level inputs but had the same result. Does anyone have any ideas about what's going on? Any help would be greatly appreciated.