As I read OP's post he prefers HDMI to the Onkyo AVR to analog to the Ayre preamp regardless of source. As I understand it, with HDMI, the Onkyo DACs are invoked but the source may or may not do some processing (e.g. converting DSD to LPCM); with analog the source is dong all the processing. For different reasons than Edorr's, I agree with him that the solution may be to look downstream. Maybe OP just prefers the sound of the Onkyo AVR to that of the Ayre/Parasound or maybe it's the Sliverline to the B&Ws, who knows short of replacing components one by one. I'd satrt with a modern high quality prepro that accepts HDMI and processes DSD as well as the lossless codecs that can be wonderful for music.
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