Issues when using Xbox Controllers on Steam Deck atleast

[DommTheDon]

I noticed when I tried to play both Halo Reach and Halo CE on a steam deck displayed to a TV using two wireless Xbox controllers that I could not get player 1 controller to work when I had a split screen active with player 2.

I could not get it to work to be able to play.

I couldn't get the "mouse" to select the mod menu to work using the controller until I tapped the touch screen on the steam deck (maybe this is what would lead to the problems later). Once loading in player 2 and starting a campaign only player 2 could move with 2nd controller selected for them. I could not move player one with player one controller selected. But, if I tapped the steam deck screen it would fire the weapon and move around where tapped on screen. However, when opening back up the mod menu the 1st player controller would move the mouse. Once removing player 2 or having player 2 use player 1 controller it would then work. But, player 1 controls in game would not work with another split screen second player.

[WinterSquire]

Did you unselected "use k/m" checkbox for player1?