http://forum.cyberlink.com/forum/posts/list/17797.page
The problem is HTPC -> TV worked. HTPC -> Amp -> TV doesn't work.
I suspected that it could be a resolution switching issue when going through the Amp so I uninstalled the ATI drivers, ran PowerDVD to play a BD and it worked (full test at end of post).
The issue is the ATI HDMI Driver, which driver should I be using ? What should the settings be ?
Full test
Remove ATI drivers (BD plays but only stereo)
Install Realtek 2.6 (PDVD crash)
Remove Realtek 2.6 (BD plays but only stereo, therefore indicates could be ATI HDMI device driver issue)
Install latest ATI drivers (PDVD crash)
Remove ATI HDMI drivers (BD plays but only stereo)
Install Realtek older versions back to 2.49 (PDVD crash)
Remove Realtek and ATI drivers (BD plays but only stereo)
Installer all older versions of ATI drivers back to 11.2 (PDVD crash with ATI or Realtek HDMI drivers installed)
Remove all Realtek and ATI drivers
Install latest ATI drivers, change output settings, tried all settings from 16bit, 44Khz to 24bit, 192Khz (PDVD Crash)
Conclusion PDVD will only play BD when the HDMI device driver is uninstalled and using default Microsoft driver.