Smash 3DS Glitch in Smash Bros. 3DS

[SmashBros50]

My music in and on the roster of smash run just simply doesn't playy. I checked the sound test, and the music is shown to play at its default setting. Does anyone know what's happening?

 

[Starman15]

Main Menu->Smash Run->Select Music
Pick the songs you want in there. There should be checkmarks by the songs you picked.

 

[Squadaloo]

I know you can control which songs play during Smash Run, so maybe you accidentally have them all turned off?

 

[AsymptoteG]

At one point in Smash Run I got an invincibility star and then all the music stopped playing until I finished that run. No invincibility jingle, no BGM, nothing. Just smashing sound effects and character noises. It was pretty weird.