If the display reads “MULTI CHANNEL” when playing a Blu-Ray disc, rest assured the Rotel processor is still receiving an HD audio signal from the Blu-Ray player, it is just being received in the form of a multichannel Linear PCM signal instead of the raw Dolby TrueHD or DTS HD bitstream. All HD signals, whether it be Dolby or DTS, first come off the disc as an HD bitstream which must be decoded and uncompressed into raw digital audio (Linear PCM). This first step of decoding and uncompressing the audio can be handled either in the Blu-Ray player or inside the processor and there should not be a noticeable performance difference based on where this occurs. With HDMI 1.1 devices the decoding must occur in the Blu-Ray player, but starting with HDMI 1.3 the raw bitstream audio can be sent to the processor.
Check the settings in the Blu-Ray player’s setup menu for an option to set the HDMI audio from LPCM to Bitstream to let the Rotel processor do the HD decoding.