What do you mean you don’t use the Retroarch one? I hit the X key on start and I have 4 emulators to choose from:
Ir-Mupen64plus
Mupen64plus-gles2n64
Mupen64plus-glesrice
Mupen64plusGLideN64
Ir-Mupen64plus is the only one that plays sound, the other don’t but play smooth. At the start of Mario Kart the Nintendo logo comes up and spins with the sound of a car, but the sound is awful, hows yours?
Retropi 3.2.1