Yesterday my LSiW sub-woofer arrived and last night I replaced the PSW404 with it. After hooking it up I turned it on with the power switch set to "AUTO". I turned on my amp and as soon as audio started the sub's LED went from red to green and everything was fine.
Since I had other things to do I turned the amp off and returned a couple of hours later. At this point the sub's LED was red, which is what I expected since it is suppossed to turn off if no audio signal is detected. I then turned on the amp and DVD to continue watching (again) season 2 of the Sopranos.
At this point I thought that something didn't sound right and looked at the sub. The LED was still red. It din't detect audio and turn on. I reached behind the sub and flipped the switch to "ON" and the LED went green and everything was then fine.
I guess I can live with having to manually turn the sub on/off everytime, but it would have been nice if it worked longer than a few hours before it broke.
Of course what do you expect for $900? :)
On another note, although this is subjective I think that overall the audio sounds "better" with this sub. It is wired inline with my LSi15s.