Recently purchased and then returned an M33 at a cost of 15% for "restocking". Confess to being foolish buying one given all the concerns. In my case my JLA fathoms would NOT function with the M33 no matter all the tips/tricks I tried, NAD support, dealer support, reading and re reading this discussion. At some point I thought, why am I going through all this crap with a $5k audio product? It should work! How could they ship out these units with a 1.1v subwoofer output? It appears that the weak sub out problem has been addressed in the new M10v2. Oh well, live and learn, I went to an STR preamp for bass management and it works like a dream (ARC Genesis is night/day easier to deal with compared to Dirac).