Feature Request: Don't switch audio to wired Playstation controllers

[TiZ-HugLife]

Your system information

• Steam client version: 1738026274
• SteamOS version: 3.6.21
• Opted into Steam client beta?: Yes
• Opted into SteamOS beta?: Yes
• Have you checked for updates in Settings > System?: Yes

Please describe your issue in as much detail as possible:

I'm using a Steam Deck for fighting game tournaments, especially our local weeklies. It works really well, except for one annoying thing that has been present from the very start: every time a Playstation controller is connected via USB, the system switches both output and input to it automatically. I think it's very valuable that it's possible to do this, but I don't think it's good default behavior.

I thought an easy fix might be to add these controllers to the blocklist for the switch-on-connect module, but that module doesn't even seem to be loaded by PipeWire, so I'm not sure what to do about it now. I thought I should go ahead and file this issue since apparently nobody else has.

Steps for reproducing this issue:

1. Dock a Deck to an external monitor with audio output
2. Have audio output
3. Plug in a DualShock 4 or DualSense controller
4. Lose audio output
5. Go to audio and see that the default outputs and inputs were switched to the controller