Just got my m50x today. Heard great things about it and finally got the extra money to buy it. Currently trying to get the burn in going through some constant listening.
Using my Nexus 6 with Neutron Music Player and Viper4Android. Easily the best sounding set up I've ever had. With the flac files I have (hip hop, isley brothers, and some other random files), my ears are pleased
Yay, I'm glad you're enjoying your M50x! The M50 sounds fantastic out of portable devices, I have to say. The best I've ever heard it play was out of a Sansa Fuze. (M50x is basically the same).
Just watch out for the M50(x) haters out there, man. They grow in numbers by the day. But then again, so do the fans.