@Hemps, I tried with my old Sammy earphones and the music playback seemed decent.
I won't lie and say I noticed a difference with the 3 songs I used for comparison between the ReNo2 and my old Moto G and Lumia 1320. The music does seem overly bassy though but that can be tweaked with the equaliser (Songs used were all 320kbps mp3). EDIT: at louder volumes on quieter songs (Wish you were here by Pink Floyd) the sound is quite hissy. It goes away below around 65% volume though
You can also select preset settings for the Xiaomi earphones but it's also only just different equalisers that are applied depending on which model you pick.
I'm sure throwing on a pair of Sennies will show it's flaws a lot clearer than my 5YO Samsung earphones can, but other than the overly bassy tones I couldn't find anything to complain about.