[Elecraft] KX1 VFO Issue

[ab2cj]

All:

I purchased a used KX1 and noticed that the rotary encoder behaves 
erratically on occasion where it will momentarily fail to change 
frequency when turning the knob.

There's some play in the VFO shaft which maybe the cause of the problem. 
The serial number is 666 which seems like an early model and I was 
wondering if there's a history of a bad batch of encoders shipped at 
that time?

Thanks,

Tony -K2MO