Input lag: Could a ''speculative execution'' feature be implemented in Retroarch?

I’m so confused. Is the audio in super mario world supposed to be this delayed even in kms? It only seems delayed when pressing buttons. And it just somehow still doesn’t feel good at all, indicating that the input delay might still be similar.
edit: Damn it the upload is corrupted, wait I’ll upload it again later. edit2: Tired again and it keeps getting corrupted, wtf. edit3: https://soundcloud.com/dylstew2/supra-mayro-audio-lag At the last part of the track I reduce the audio latency setting.

edit2: I don’t know how you guys did it, but the retroarch version of desmume can run Rhythm Heaven/Paridise without noticable audio lag 0.o. I can’t achieve that on standalone. The problem is that I can’t turn the screen around because that also turns the mouse around, haha.