Here goes: I know I need AVIA, but for now, I am trying to use THX OptiMode to balance my speakers. The one from T2 varies wildly from the one on Castaway, and THEY both vary from my receiver. I am NOT trying to set 'reference level', just the level between speakers. For example, I used T2 OptiMode, set the levels equally, then tried the OptiMode from Castaway, and the readings were VERY different. Surrounds down in level 5 db from the fronts, etc. Should the discs vary like that? Is there one THX OptiMode movie disc that is known to be correct? Or should I just use the receiver tones for now, until AVIA arrives. And why do we put ourselves through this?