Guys I started this because I am having an issue with my SNES when trying to play SMK 2 players.

I have 4 controllers and 2 seem fine and 2 are playing up.
I have done some testing to come up with this idea and it has me thinking that it may be the "Latch" wire in the problem controllers.

- Using any single controller by itself 1 player gives me no problems at all.
- Using both known good controllers together gives me no problems at all.
- The 2 problem controllers always cause false inputs for the other "good" controller.


So this is how I first found this and how it always happens since also.
- On March 11th I had a N64 20th anniversary party, as the night was finishing my cousin pulled out the SNES (first time in a couple years) and was playing SMK, 1 player (with a bad pad, works fine 1 player remember)
- I challenged him and plugged in a second pad at that time (my pad was a good working one)

- At the character select screen we realised the issue
- The bad controller does its correct player inputs fine but messes up the other players inputs.

- The messed up one would now do these things,
 - "B" button now shrinks player ("Y" and "A" together)
 - "R" button now does other player "Start" and "Up"
 -  Definitely some other issues also

Once in the race its obvious its a major problem that can't be ignored.
When the problem controller is unplugged the other "good" controller will work perfectly and as soon as the problem one is plugged back in the issue comes back (seems to be the exact same button errors etc everytime).
Switching between good and bad controllers mid race will switch between good and bad inputs immediately.

Very confusing at first since for a while we thought the good pads were bad and the bad pads were good since the error is passed over to the other players controls.
It does not matter who is player 1 or 2, if a bad controller is plugged in it will interfere with the other players inputs.

Bring them along and ask Daniel Guemy (FFVIMan) to have a look, would recommend getting some new controllers asap on ebay.