[Elecraft] K1 sidetone problem

[David L DuPuy]

Has anyone else had any problems with the sidetone on the K1?  I've just
finished building and at low power (0.5 watts) I have heavy key clicks when
sending.  At higher outputs, I'm getting a dual tone with heavy clicks,
sounds like RF is getting into the audio.  The problem is worse on 20m, but
it's a big problem on 40m too.  Any ideas on where to look for a problem?
 The transceiver appears to be working normally otherwise.  thanks, David
AC4BN