Question about overflexing the racket shaft..

With DinkAlot's breaking so many racket shafts, I'm wondering how well extra flexible rackets will tolerate an average power player's swings?

I've seen an ISO 75MF broken at the shaft in the past by a friend, and I'm wondering if the same fate will happen to my Carbonex 8000. I'm hearing clicking sounds at the cone when I rapidly swing the racket back and forth. I've bought the racket for only 3 weeks and used it on an irregular basis.

Normally I use my AT500, which I've had for a bit over 2 years now. I prefer head light/even balance rackets, and the Cab 8000 is meant to be a temporary solution, and as a backup racket that I can lend to others, until I'm ready to buy another racket.