Holding A/B/X/Y after a tap also presses pause button

I have a weird interaction that’s started recently.

When I double tap one of the above buttons and hold it, it also triggers the start button. I’ve confirmed this by doing a text and pressing the buttons in that way, it highlights the button I’m pressing plus the start button (three dashes). It’s making some games pause while I’m playing. I’ve gone through every option I can find and nothing is fixing it.

I’ve also just moved to Bazzite - and the problem is persists.

Any ideas?