YAMAHA RXV 3900 questions/issues

My bedroom AV system consists of a Yamaha RXV 3900 receiver, a Panasonic DMPDB35 blue ray player, a Directv HR 22, all feeding a Sony 46 XBR6 wide screen tv. The RXV 3900 also feeds a Sony KDL22L4000. All interconnects are accomplished via HDMI cables. The RXV 3900 does a good job of feeding both TVs, either simultaneously or one at a time. The RXV 3900 also decodes Dolby Digital sound from both the DVD player and the Direct TV HR 22 DVR. I have the following questions:

If either TV is on, the Dolby Digital decode works fine. If both TV's are on, the RXV 3900 reverts from Dolby Digital to Pro Logic. Should I turn off one of the two TVs, the RXV 3900 reverts back to Dolby Digital.

Secondly, if I put a DVD in the Panasonic DMPDB35 DVD player and select Dolby Digital for audio, the RXV 3900 correctly decodes it and shows it on the screen.

Should I change the audio to DTS (verified by checking the DVD player audio screen), the RXV 3900 shows Pro Logic. I show that the RXV 3900 supports the DTS format, but I can not get it to decode it from the DVD player.

Any ideas how to accomplish this? I have the same DVD player and TV in my living room, supported by a RXV 4600 and it automatically decodes the DTS and show so on the screen.

Thanks in advance for the help! Also the RXV 3900 manual leaves a lot to be desired. Any better information resources?

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Okay everyone, an update:

I rented "Knowing" on blue ray, which supports the DTS-HD audio. When I check the audio selection on the Pannasonic Blue Ray DVD player, it correctly shows DTS -HD master. The RXV 3900 shows only DTS and nothing about "HD" Is this normal when using a 5.1 Bose Acumass speaker system? Do I need instead a 6.1 or 7.1 system to get a DTS HD from panel indication on the RXV 3900?

I am using HDMI between the Blue Ray player and the RXV 3900.

TIA

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