I have a pair of Klipsch X7i iems which seem to work fine when plugged into my ipod touch. However, when I turn the volume up past half way they start to distort in a sratchy and sibilant way. I have a few pairs of these and they can handle the volume all the way up without any distortion so I know its not that the output is too loud. Normally its jack failure that I repair with this particular model but my gut instinct tells me that this is not the case here. Is it just a sign of defective drivers on their way out or a pair that have been overamped in the past? Any ideas?