I read your reply with interest as I was thinking something similar. I removed the encoder and cleaned up the solder pads squeaky clean.
I saw some flux crud and stuff on the encoder case so cleaned with 91% alcohol,? and I put leads on the 2 pad side I suspected was the issue.
All said and done, Nada...push button works, but now no tuning at all, up or down. rest of radio sorta works but once I saw no tuning, well I put it aside for today.
I have a couple of new encoders coming Monday from Hans anyway...wait till then.
73
John-N2LK
John Schreiner