[Elecraft] raspy cw audio on K3--but OK after power cycle

[Rocky AE7US]

I just turned on the rig, went to the CW portion of 20 meters, and when I
tuned in on a strong CW signal, the audio was raspy and distorted.  After
turning the radio off and then on again, the signal sounded normal.  Any
ideas?

Thanks,

Rocky, AE7US