[Elecraft] Anyone else experience K3 keyer hesitation?

[Andrew Moore]

WA5BDU> I will say that I have had the K3's keyer misfire or hesitate while
the K3 was being bombarded with serial interchanges from HRD and/or N1MM.
This surprised me because I thought the keyer would have a very high
priority.

I've noticed the keyer hesitate on two occasions since I got my K3 a few
months ago.  Just a bare K3/100, no serial port activity, etc. Very slight
hesitation on a single Morse element -- but noticeable.  I wouldn't say it's
a major problem, but has anyone else (besides 'BDU) experienced this?