I am trying to play this game with an xbox 360 controller for PC. I got the joystick settings right where I wanted them by tweaking the configuration settings and I am using the built-in DOSBox keymapper. I had set A to be Alt and B to be Space (Alt is jump, Space is shoot). However, when I did this, pressing either button caused Jazz to jump AND shoot at the same time, every time.

I tried changing the bindings so that RB is space/shoot and A is Alt/jump. This makes it so I can shoot without jumping, but pressing the jump key still causes Jazz to shoot. Not sure why this is happening.

Solved it! Apparently, the game will automatically read the Xbox controller as a game pad and automatically assigns functions to the buttons. B is automatically the shoot button, A is the jump button and X is weapon switch. The only issue is that X is a bit fussy and doesn't always work, but other than that the game controls well.

I think the issue was trying to alter the keybindings via the DOXBox binding tool.