Out of all the emulators I use, citra is the most problematic. It runs pretty well on the steamdeck but with a bit of a lag when loading new areas. It catches up almost immediately, though. Could totally see a remastered SMT4/A and Strange Journey getting a steam release at some point.
On topic: check your bios and firmware to make sure they are compatible. If it's not booting at all, I'd bet it has to do with that.
That or Retroarch set to GL instead of Vulkan. It's a bit of a double post from last week's 3DS thread, but I'm in the same boat as you are regarding the few stutters... IME The culprit is shader and texture caching. To alleviate the issue :
- I run Citra's folders on a SSD.
- With the Vulkan renderer (allowing SPIR-V shader gen)
- I tweak options like Shader JIT and Async Shader Compilation depending on the game.
- You could also find already compiled caches online for a few games and unzip those files in the game folder. There's instructions on how to do it here.