How did you do your workaround and get your PS4 send LPCM over 48kHz? Without going over it your amplifier will kick between signal and do its own magic to it, adjusting levels adding extras etc. DD5.1 native is just fine, better than modified LPCM. Only direct source what you can pass thru on that is analog audio via "multi channel input" with RCA cords. Or getting over 48kHz LPCM working thru it.