So I've never been able to find a straight answer to this question online.
This question is for those of you with a Xbox 360 Slim, HD-DVD Drive, a surround sound receiver capable of decoding DTS-HD or Dolby TrueHD audio codecs and everything connect using HDMI.
With the above setup. When you play a HD-DVD does the HDMI port on the Xbox 360 Slim pass the uncompressed HD audio through properly? or does it dumb it down to Dolby Digital/DTS like the original Xbox 360 does?