You experience no change in volume when cycling through channels with your Direct TV? Maybe it has something to do with ones location within the satellite footprint as the neighbor has the same experience with Direct as mine with Dish. Switching from HD to SD channels will normally have greater differences leading me to think it has to do with the audio format changing and how it is handled by both the Dish/Direct receiver as well as the Outlaw.

Everyone feels differently of course but for me if Audussey is the only solution I would rather live with the problem. I might just be one of the lucky ones who can get by without it but Audussey brings little if any benefit in my room. Room treatments take care of everything save the lowest frequencies where Audyssey is no help. Everyones experiences and rooms are different of course so what works for me may or may not work for others.