Classic Limited Background FPS not working all of a sudden

I have my background FPS set to the default of 30. However, I noticed a couple days ago that it was not working, as when I tab out over to my second monitor, I can tell that the FPS does not go down in-game. Additionally, my GPU fans will usually get a bit quieter when I do this, but they remain the same speed. This never really happened prior to DF pre-patch, and I think it worked for a couple days after and only really noticed it occurring on Friday. Has anyone else ran into this issue or know a solution? via /r/wow https://ift.tt/hjrmz1E