The music in the controls menu and secret level will be quickly removed from the game in an update because it’s made purely with stock loops, therefore it’s not an original composition. I believe it violates Newgrounds' rule on stock loops, but i don’t know since it’s in a game and not in an audio format. It’ll be removed regardless, i only want original music in the game after all. The rule states:

“There are plenty of pre-made loop packages available. Simply mixing these loops isn't your own original work; you will need to make more effort to create something unique.”

The tracks in the controls screen and secret level are not original compositions.

This update will only serve to removing these tracks and replacing them. Nothing else has been removed or added.

Also, you should check out @BoomKitty! His song “Firewall” is featured in the game under a Creative Commons license.