Anyone with prototype Xiaomi M2 and quality headphones? Help, please! I have a hard question: does Xiaomi M2 (and M1S/M1S Young edition) make background noise when you connect a pair of low resistance (impendance?) headphones? Mine are Ultimate Ears Super.Fi 5 Pro (dual drivers). Most phones I tested don't have this problem, but recently I bought HTC Desire X (couldn't wait any more for Xiaomi M2) and it has this annoying noise even when I lower the volume to zero. No music, loud noise. Hissing sound? I returned the phone the very next day, that sound is unbearable for me. Any info is welcome!