So, i tried many different dvd players, but the problem stays at it is. The one that is causing my problem is definetely the Yamaha RX-V1400. What a shame. You spend about $800 on the rec and what you get is a product that fails on playing simple DTS on Alien. I´ll write an email to Yamaha to...
I can´t confirm your problem, but i have a smiliar one on my Pioneer 535. When i chose to watch the first part of the Alien Quadrilogy Box in DTS, my receiver jumps from DTS to Pro Logic II and back, so that i could not hear the movie in DTS. DTS does work fine on Part IV, but not on Part I.