I'm testing this amp for a week before deciding whether to keep it. At first I was a bit underwhelmed, but now it's sounding a lot better and with 2 days letf I'm unsure. I'm pretty sure I would keep it if not for some problems with it's funcionality. 1. I can't get it to output to the sub when playing stereo sources. The sub plays LFE for DVD 5.1 tracks, and operates fine with the amps test tone. The SW box is there on the display when playing stereo, but not lit up. And in the manual, it says that in stereo the signal is sent to the front speakers and the woofer. Is something wrong with it or am I missing something? 2. I can't see any way to set a crossover frequency for the sub. 3. I liked the option on my old amp to set the speaker distances. With the 540R, you can only set delay times, and only in steps of 5ms. I liked knowing that my old amp knew the exact setup of my speakers.