Hey Shaddura, the weird crackle has to do with the engine (pico-8), I noticed it on my wireless headphones, but my other pair don't have it. As far as I know, there isn't a fix :S
With the out-of-sync comment, I'm not totally sure what to say as the notes are directly linked to the music and shouldn't be out of sync; However, I do agree that it feels a bit disjointed but it felt very empty without any background beat. Something for me to consider when I'm redoing that path and working on the others though.
Thanks so much for the great feedback!