Just my $0.02. I have the same problem on my passenger side door handle. I am going to go with the brake fluid/cleaner theory. Evidence; while looking at a different vehicle on another lot, I got some "oil" on my hands which I thought was armour all or something. After a while, for some unknown reason my sunglass ear pieces literaly started melting (2 years old at the time). Didn,t pay much attention at the time, I just wrote them off. Fast forward to last week, I had my X5 detailed, and my wife noticed the passanger side door handle was "gooey". I have not been able to find anything to deactivate the melt process, so it looks like a new door handle will be on order. BTW great site.