Help!! Just sat down to watch LOTR on Bluray hoping to get 6.1 sound but all I'm getting via my Onkyo 605 is 5.1Checked all the settings - DTS HD-MA 7.1 works fine, so does DTS ES 6.1, but nothing from the rears on HD-MA 6.1. Checked with a couple of other discs and they don't work either. Have I got a problem with my amp or can it just not decode this format??