Has this ever happened to anyone?

Take your device and start playing music on the main music app that comes with the phone/tablet.

While the music is playing, open up FE Heroes.

The voices will sepound deeper, like the characters are demons or possessed while the music slows down significantly, kind of like a demonic presence ruined it. If you close the music app (but not FE Heroes), it'll still be that way. Close FE Heroes and reopen it, and it'll work normally.

Just wanted to let you guys know, in case this never happened to you.