[noggin]

Thanks for the response, my knowledge about the Conversion to PCM quality by openelec is limited, would I achieve the same quality basically having everything output as PCM ?

Yes - with a few exceptions. Decoding HD Audio to PCM is lossless, and should deliver identical quality in many listening situations. The original PS3 does the same with Blu-rays with HD Audio, it decodes and outputs as PCM losslessly.

Before HD Audio decoding was standard on most HDMI amps, a lot of amps only had PCM 5.1/7.1 and DD/DTS audio inputs (I had a Sony 5.1 HDMI AVR that worked like this), and Blu-ray players decoded HD Audo tracks to PCM.

All that is happening is that Kodi is decoding HD Audio to PCM instead of the Amp doing it. (It has to be decoded to PCM somewhere...)

The limitation is that some Amps in some modes will use the metadata embedded in the HD Audio bitstream (which won't get to them in a PCM decoded stream) to do additional processing. This could be for 5,1<->7.1 up or down mixing, or for reducing dynamic range or boosting dialogue when listening at lower volumes etc.

However for most HD Audio there is very little difference - and in many cases the quality is identical. The only limitation on the Pi 2 is that 192kHz output is limited to a maximum of 4.0 - so the very rare 5.1/7.1 192kHz tracks (like Akira) will be downsampled (not sure if to 48 or 96kHz) 5.1 or 7.1. Stereo 192kHz stuff will be output at 192kHz I believe.

(Cubox wise the forums are pretty much graveyard but shifting topic away from that)

Yep - and I'm not sure if the Cubox or Cubox-i support 5.1/7.1 PCM output - or whether they are limited to PCM 2.0 and DD/DTS like a lot of ARM platforms (the AMLogic stuff is PCM 2.0/DD/DTS only).