i had the ue900 and sold them, i didnt experience any problems with mine except the unbearable distortion at high volume, replaced them with westone w40 and much prefer the fit and cable, the ue900 has slightly better highs as the westone can be sharp, kind of on the lines of sony ex1000 sharp at times, it is detailed and clean most of the time but the ue900 was smoother and never spiked. the bass tho, the westone have the ue900 beaten here for sure. its clean, and displays more bass, certainly a warmer headphone and about the same extension as the ue900, both dont extend as well as the ex1000 but the westone has the most quantity of bass of these and its perfectly to my taste so im very happy with these now. besides the fit and finish of the westone is first class. i had reservations about the epic cable because it seemed so thin but its brilliant, the ue900 has thicker braiding but it tangles like hell, the westone hardly tangles at all and is so comfortable even more so as it has no ear hooks or guides.
anyway ill save my westone w40 review for another page.
the ue900 was a nice set of in ears but looking back they are clearly not the best made, i mean those non gold plated connectors have been telling a story for some time now, not a good one. i liked the cables but they were tangle prone, the case was nice but not terribly secure, the westone case as reference is much more secure but not as pretty and a bit small.
the biggest flaw for the ue for me was they just couldnt be driven very hard, again in comparison the westone are blisteringly loud and clean at any volume and its just nice to know that in your mind the drivers can handle whatever you throw at them, the ue900 just didnt fill me with that confidence and i just knew the bass drivers just couldnt take it, is this the housing, the drivers, the cables blah blah who knows. it just wasnt great.
its a shame because a bit more time spent on quality checking these could have been excellent.