Wico joysticks

[Oldsmobile_Mike]

I think you've got a CIA chip issue.  Try the joysticks on another system (even an old Atari or C64, anything with the same connector), or try a known-good joystick on the same system.  But cross your fingers, maybe it's just the joysticks and a good cleaning and adjustment of their innards will do ya!

[Oldsmobile_Mike]

Pretty sure they are SMD on most A4K motherboards.  A few people have had them replaced and had sockets added in the past.  You'll have to check your particular board.  On some models of A2K there's an inline fuse as I recall that can sometimes act up, not sure if this exists on the 4000's, as well, or not?

Also do the obvious - check for battery damage to any traces, bent pins inside the connector, loose solder joint at the connector, etc.

[Oldsmobile_Mike]

The Fire buttons (on the stick and the base) just stop working sometimes. In the past I have turned off the computer (originally used it with a C64), unplugged the joystick and plugged it back in, turned the computer back on and then it worked again. I opened it up way back then and never found anything obviously wrong. The feather switches are in pretty good shape with only minor wear. Since they both fail at the same time, I am inclined to believe it is something with the 9 pin connector and nothing to do with switches.

This is good troubleshooting procedure here, but what I would do is test the controller with another computer.  And test another controller with that computer.  That should narrow it down to exactly if it's a problem with the controller, or with the computer.  Good luck!