In the latest snapshot, when creative mode music plays, switching your gamemode no longer stops the creative mode music playing, even when switching into survival mode (tested in a  new superflat world).

This can cause creative mode music to play in survival mode.

I found that there was a bug report saying that the music shouldn't stop, but I also found a comment saying that it was working as intended.

Here are the links:

MC-36501

https://bugs.mojang.com/browse/MC-42711?focusedCommentId=126420&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-126420