If like me you need to grind out your last songs sung after getting everything else theres a way to speed things up.
First make a playlist by pressing
on songs in the party mode song selection screen, once you have enough in your playlist press
to open the playlist and scroll all the way right and press
to start the playlist. Once a songs starts wait 10 seconds and then you can press
which brings up the pause menu, you should have 3 options - Start Over ~
Quit To Results ~ Back To Menu.
By pressing yes on 'Quit to Results' you end the song and get your results which then adds a song sung to your counter, then just start the next song and repeat.
Note: If you pause too soon the option to quit to results will be missing and your choice will be to start the song over.