still under warranty? Talk to the etymotic service dudes.
Toll-free 1-888-Etymotic (1-888-389-6684)
Hours: 8:00 AM - 5:30 PM CST, Monday - Friday )
I had my er6-i's for almost a year and going strong before they met their untimely demise at the hands (jaws) of my dog.
EDIT: stupid question, but have you ever replaced the filters on those er6-i's of yours?
Oh, and also, I have replaced the filters. I thought that could have been the cause of the problems.