I have a Sony bdpS1 and a Toshiba HDA30 connected to the Onkyo 805.
How come HDDVD's with Dolby TRU-HD sound a few notches quieter than Dolby TRU-HD encoded Blu Ray discs?

Does the signal get unavoidably dial-normed on the Toshiba, mind you I turned off all audio alterations in the Toshiba's menu.