I've never had any issues with the standard three emulators - MAME, Daphne, and Visual Pinball. But with AAE it seems to spend some time trying to render the screen, which ends up being a bit smaller than the game list image - whereas AAE loads straight in about two seconds from the command line. So there must be something non-generic in how Mala handles each emulator. OR Mala handles each emulator in a generic way that interferes with each one's natural command line loading.
Now all I need to work out is why my sound just disappears!
I've found it depends on your audio settings (repeat, shuffle, etc), and how long they are and whether they have long bits of silence in them or cueing; as well as what kinds of audio files you have
selected - if it's one Mala doesn't support, Mala might stop play rather than just skipping it.