how does this work? i have the example of Ballistic: Ecks Vs. Sever. this is a non-EX disc. however, 1) my amp (Pioneer VSX-D811s) displays EX. and 2) there are scenes where the back center speaker plays stuff that isn't in the left or right backs. specifically, machine gun shots at the 31:08 minute mark. so in other words it sound like an EX disc.