Real karaoke

From Performous

In FOF format songs you may find many tracks like: drums.ogg, rhythm.ogg, guitar.ogg and song.ogg

In this case, song.ogg will keep all sounds different than drums, bass and guitar. That means that in many cases, song.ogg will just keep voice and maybe some other secondary sounds (you can check it hearing to that track). If you rename this file "song.ogg" ----> "vocals.ogg" then you can mute or activate this track while playing using "CTRL+v" or "CTRL+SHIFT+v". Note that the vocals track will be activated as default when the song starts.

There's a script you can find in game's folder which you can use to do this in all songs that have many tracks. Then you can mute the track while singing and, if you see too much is being muted (for example if the track keeps an important track as a soloist flute xD), you can activate it again and continue playing.

Try combining this with Microphone Pass-through !!