[Elecraft] broken AF knob

[r miles]

I've only had my K3 #2626 5 months. The AF knob loosened today. When I finally found an alan small enough to tighten it the knob split before it was even snugged up. Not cranked. Wasn't there a thread about this about the time I purchased my K3? Is this a common problem? Is there an improved knob available?
I just sent Elecraft an e mail so I hope to get their reply Monday.

K9IL