On regular DVD's in 5.1, do I get 7.1 when I use DD EX? Or do I have to use PLIIx on these 5.1 DVD's to get 7.1? On DD EX DVD's, I assume my THX ULtra2 automatically picks up the EX content? Yes, I have 7.1 speakers! (3fr, 2 surr sides, 2 back, sub)