Update 26/10/23 15:54 UTC: Valve developer Pierre-Loup Griffais mentioned on X that Proton Hotfix was updated to help but it's still not fully solved yet without the fix in the guide below:
A Proton Hotfix has been deployed for "METAL GEAR SOLID 2: Sons of Liberty - Master Collection Version" and "METAL GEAR SOLID 3: Snake Eater - Master Collection Version" to address a blocking crash in cutscenes. A fix for missing audio in cutscenes is still being worked on.
For the impatient, it turns out there is a way to make METAL GEAR SOLID 2: Sons of Liberty - Master Collection Version and METAL GEAR SOLID 3: Snake Eater - Master Collection Version actually work on Steam Deck and desktop Linux since they're currently broken.
The best way would be to wait for Valve to roll out an official fix in Proton, but if you really can't wait the fix is relatively simple. Thanks to sleuths on the GitHub bug report you just need to get a copy of xaudio2_9.dll either from a Windows install, a different game or other methods like this website (use at your own risk, and get the 64bit version).
For Steam Deck, you'll need to be in Desktop mode (Steam Button -> Power - Switch to Desktop). If you downloaded it, make sure to unzip / extract the file, then in Steam on MGS 2 and MGS 3 right click -> properties -> installed files -> browse to open up the file manager. Then place the xaudio2_9.dll inside each to sit next to the main exe files.
After that, on each game set a launch option via right click -> properties and put this in the box on each game:
After that, you'll find that they launch, but there's probably other issues but for now at least that will get each game to work. Some issues I saw include:
- Overblown audio in MGS 3 that sounds distorted.
- MGS 2 and MGS 3 on desktop Linux run way too fast, you'll need to find a way to cap the FPS. You can use Gamescope for this to cap the FPS to make them run normally like so:
WINEDLLOVERRIDES=“xaudio2_9=n” gamescope -r 60 -- %command%
Here's a video doing it on Steam Deck: