Strange Problem with my Genesis Controller

[LentFilms]

Hello, I recently got a new Sega Genesis to replace my broken one but I am having a strange problem with the controller. Whenever I press the start button nothing happening but when I press the C button it acts like the start button. I do not think the controller or the game is the root of the problem because the problem persists no matter what controller I use or what game I play. The cause of this issue must have something to do with the genesis hardware itself. Can anyone tell me what could be causing this controller issue and how I can fix? Thank you.

[Hobie-wan]

See if there's anything metal that's gotten into the socket on the system that's shorting. If not, open up the system and look for any issues around the back of that controller socket.

[OmegaMaximum]

If you feel adventurous, you could open up the Genesis and see if anything is possibly in there shorting the connection between the controller port and the motherboard, also see if the player 2 port does it as well. If it does then you might consider yet another Genesis.