Hi guys, As I see there is a HDMI IN port, I am very curious that if I have a cd player and connect it to X20 pro via HDMI IN, ...... 1.) Does X20 Pro accept any external source via HDMI IN? 2.) If yes, that means Sabre DAC will improve the audio from that source too, right? 3.) Does X20PRO itself accept USB DAC? thanks million times.