[Elecraft] [K1] Tuning Jump Cause

[Curt]

My K1 has developed a glitch.  Sometimes, while tuning, the displayed 
frequency will suddenly jump down about 10-15 kHz, then return to the 
correct frequency.  I hear some static in the headphones at the same time. 
The jump isn't caused by tapping the case, only moving the tuning knob.  It 
doesn't seem related to a specific "spot" on the pot.  Without rotating the 
tuning pot, there is no frequency instability at all.

Ideas?  Curt KB5JO