I just had my Gustard U12 delivered and when coupled with my SMSL Sankrit Pro-B DAC, the sound is very good when playing WAV, FLAC music. However, DSD music can not be handled by this pair, unless I get something like X12, which can process DSD via i2S input using the HDMI cable. I have some good DSD titles that I need to listen without switching USB input all the time (Sankrit can process DSD). I've heard a lot good thing about X12 and I will need one to make my system complete. Let's make this thing happen.