It could be your headphones, but it could also be that you are running out of your music player too loud and your fiio not loud enough or vice versa. Try playing with value ratios, some different headphones, and first of all some different music files in FLAC or 320.
Hey guys, thank you for all your replys. Well the clipping is both heard on my sony xb500 and xb700 headphones and it only happens on the bass, at high volumes. So whats your opinion on this situation, is it the headphones that cant take the bass or the amp clips the signal at high volumes? Somebody also said on headfi that there headphones, the m50s clip past 6 on a fiio e11, on high gain and bassboost set to 2, so i am not sure if its my headphones or do i need a better amp to drive them with clean power?
Someone else mentioned the player too, what player are you plugging the E11 into and what's the volume setting on that? Sometimes too much input volume could cause clipping. I bypass that by using a line out adapter to connect the my iPod to the E11, which connects to the dock output instead of the headphone jack and bypasses the iPod's internal amp.