Router Runout Gripe

Ok so to make a long story short…
The other day, I started using a flush-trim bit for some template work. The bit I was using was a CMT 3/4od 2” overall length downward cut bit that was part of a cabinet set. I turned the router on and felt/heard horrible vibration so I turned the router off and noticed, as the bit slowed down that there was visible runout; in the neighborhood of 15thou. Thinking that it was the bit, I called CMT an the promptly sent me a new one (great customer service) free of charge. Well the new one arrived today and the same problem occurred. I knew that the 2 bits couldn’t be bent so I started thinking about other variables that could cause the problems. Turns out that, after lots of tests with a dial caliper, it seems to be the collet in the router.

With the dial caliper, I determined that the runout of the bit right above the collet is about 5thou and at the bearing it jumps to about 15thou. I tested it on other bits with the same result including a precision centering pin from Whiteside. Also the the part that the collet screws into is perfectly round and has no runout. So, by process of elimination, I’ve narrowed down to the collet causing problems. I tested both 1/2 and 1/4”, with the 1/4 being better, but not by much(3thou and collet and 10thou and bearing).

The router is a 690 series PC.

I guess my question is has anyone else had these problems?
And how should I go about fixing the problems?

I would say 4thou runout at the bearing is acceptable on such a long bit, but 15thou makes it unusable.

Any suggestions would be greatly appreciated, and thanks in advance!

Mike