[Elecraft] harsh output note?

[Chris Kantarjiev]

I just had occasion to listen to my K2 with another receiver (my KX1) for
the first time in a long time. The received note is much ... harsher
than I'd expect. There seems to be a harmonic an octave or so down from
the main carrier, so there's a fairly complex tone coming across
rather than pure sine.

I don't often listen to my output, probably poor practice on my part.
The last time I did, it sounded better than this. With the radios reversed,
that is sending on the KX1 and listening on the K2, the KX1 sounds much 
better/purer.

The main thing I've done recently is add the key shaping mod...
which led to some power out problems that I haven't dug into yet
(the power bounces more than I'd expect, and it's hard to get exactly
5w out on the RF meter).

Should I be concerned about this? How do I go about diagnosing?

Thanks!

73 de chris K6DBG