[Boatanchors] Disc Ceramic Caps

[Curt]

Recently acquired a tired old DX-40 with keying issues. Slight frequency 
change after key-down ( chirp ), now sometimes will not stop oscillator on 
key up. So, evidently something is causing the keyline to stay low?

Don't usually suspect low-value disc ceramic capacitors like used to bypass 
the key line to ground.  Is there a failure mode for these that would cause 
them to short out intermittently?

Thanks, Curt KB5JO