It's an architectural issue.

You have a distributed architecture in the 568.2MM/G68/861. There's a DSP on the digital receiver, and it can either decode or upsample, it can't do both. So if it receives a bitstream it decodes from DD/DTS/MPEG, if it receives PCM 48K or lower, it upsamples.

Then the DSP on the digital receiver passes on to the DSP core.

Regards,

Surround Music Fan/Computer Geek/Curmudgeon in training.
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