I played the DTS-ES 6.1 encoded 'Spirited Away' with my YAMAHA RX-V340 amp, which could decode DTS matrix 6.1. the amp only generated some noise to the speakers. But this disc can be played using my friend's amp that only support DTS 5.1. I heard that DTS-ES 6.1 was backward compatible with DTS 5.1 by ignoring a track. But my amp treated DTS-ES 6.1 as DTS matrix 6.1, and could not decode it successfully, even I put off the 'matrix' light on the front panel using remote control. Could I force the normal DTS 5.1 decoder to work with disc to hear something? Please help me... thanks in advance.