K3S ideas?

[James Jordan]

My K3S has full 100w output on all bands EXCEPT 10, 12, 17. Drops to about 20 watts max when set to 100 and less at lower settings   Strangely 15 and 6 are normal. I tried pulling and replacing the amp module in case the pins were dirty or loose but it made no difference. 
I seldom use WARC bands so 10 is all I’m missing for contests. 
Ideas other than a trip to Watsonville?
73,
Jim K4QPL 

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