[Elecraft] K2 raspy side tone

[Jacob Chambers]

Hello;
I have an older K2 that has developed a raspy, scratchy sounding CW note on receive. All bands affected. The transmit sidetone is clean as a whistle. Headphones or external sparker are the same. Seems like there is some popping and scratching when I bump or play with the AF gain control. Could that be it? And I'm thinking of spraying with DeOxit contact cleaner. Is that OK? Thanks! 
Jacob K4JQV

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