[Elecraft] [K3] - KRX3 not working on 12/10

[ON4WIX]

Hi group,

Running K3 S/N 0192 here. Installed my KRX3 last autumn and up until now all 
has been working well. Of course I've only been operating on the lower bands 
during winter.
I just noticed that my KRX3 does not work on 12 and 10 metres. Not sure 
about 6m since I don't have a dedicated 6m antenna up yet.
I can clearly hear signals in my main receiver on 12 and 10 but when I 
switch the KRX3 on my right earpiece goes silent on these bands save for 
some thermal noise.
Has this phenomenon anything to do with the known synthesizer ALC 
calibration problem as described in the application note "K3 Synthesizer 
ALC" Rev A, dated December 23, 2008?

I would appreciate some info before I start heating up the soldering iron.

Thanks for any info.

73
Glenn ON4WIX / OR4W