How to mute Stepmania?

I sometimes minimize Stepmania so that I can watch YouTube or do some other stuff on desktop.
However, the background music of Stepmania doesn't stop even though I minimized it.
Is there any ways to mute it so I can watch YouTube or listen to other music?

Hold F3 and tap R until the volume is lowered to 0%, then do something that makes Stepmania update the music it's playing, like scroll the music wheel.
When you come back to Stepmania, hold F3 and tap T until the volume is back to 100%.