Hello jammers!
If you're looking for more audio assets to use on your games (other than Joshua's audio and OpenGameArt resources), I'm currently running a 50% OFF Sale valid for all my audio assets on Itchio, and wanted to share it with you: https://itch.io/s/28908/spring-sale-2020
In addition to that, I also have some short 8-bit music loops collected in my personal website, they're free to use and released under CC Attribution license: https://www.filippovicarelli.com/8bit-game-background-music.html
For even more music, check out my website PlayOnLoop.com, there are plenty of short music loops that can be used for free under CC Attribution license (just browse the website and look for the yellow button "Free Download").
To the Infinity and beyond!! :D