Had a problem with bass sounding untight, waffly at times, over-reaching. After resetting the Marantz' microprocessor, it appears my untight bass problems may be solved. When I tried to connect my son's Nexus 7 to the Marantz, it kind of froze, wouldn't connect, also wouldn't allow me to make any changes to any settings or go to a menu, at least any displayed on my HDMI TV. It wouldn't display anything other than the non-connect error code. After researching the manual on CD, it suggested when acting strange, reset processor. Did so, now the tone control is unlocked. But now, it doesn't appear to need less bass. Before the reset the bass frequencies appeared to be late, lagging behind the beat of the music. Now, not at all. I've not tested DVD movie sound, but I'd bet its a little tighter bass-wise. Before the reset, the source information would show and appeared to default to stereo/music listening mode. Now it appears to default to Auto. Apologies to Crown amp powering my diy sub, it appears the Marantz receiver, or my lack of knowing how to run it, was to blame. Don't think I'm looking to get EQ or DSP now. Reset the Marantz microprocessor.... I did buy it refurbished from A4L, it likey has needed resetting all along.