I’ve installed 20.1 nightly update, and also from coreelec repo the amiga emulator.
Something must have happened lately, because now it is too slow, and audio and video stutters everywhere, which was not the case before, when i tried the last time, 1 month ago.
On S905x4 generic device X96_X4.
Maybe some problem with PUAE 4.9.1.36.2 .
edit:
I installed from zip an older version, works much better.
https://relkai.coreelec.org/?dir=addons/Amlogic-ng/20.0/arm/game.libretro.uae
game.libretro.uae-2.6.1.34.1.zip