Can ppsspp for Linux be optimized?

[xsacha]

The SDL and Qt one should have the same performance.
Sound should be identical in both unless your distro hasn't done QtMultimedia properly. Certainly in Qt5 every distro should have proper sound. It's normal to not hear sound stutter.
This is my experience anyway. I've tried about 4 distros so far.

The Qt version is actually better because you have a real menu and ability to switch fullscreen and use hotkeys.