I found my BDP9700 had problem under bitstream playback.
I used a single HDMI cable to connect BDP9700 (main HDMI) with my AV amp (Pioneer SC-LX82).
When I played a Bluray disc by DTSHD, my AV amp was able to receive the bitstream signal from BDP9700.
If I switched the sound to DolbyHD, my AV amp was not able to receive any signal from BDP9700, and no sound could be produced.
I have set the BDP9700 as using main HDMI only and "bitstream" output at the setup menu.
The above mentioned problem was never existed when I using my old bluray disc player.
I have tried the 3.71 firmware, also updated with the latest 3.76 firmware, but the problem was still existed.

What can I do with my BDP9700?
Thanks!