Back in February, Nintendo issued a patch for Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey to fix a bug which had been known to essentially break players' save files. In an odd turn of events, this patch has actually brought with it a brand new issue, breaking one of the game's other features.
Originally, if Mario was lost from your party in the Nimble Woods area of the game, and you then went on to save your progress, the game would glitch out and Luigi would be unable to move beyond your current section. This has been resolved - Nintendo even managed to save the game files for those already affected - but it has now been discovered that the game's jukebox has stopped working correctly.
The jukebox allows players to enjoy a number of music tracks from the new game as well as original pieces from the DS release. Since the update, players have spotted that pressing 'play' on any of the original tracks now presents you with nothing but silence and, once you've done this, the other - originally working - tracks fail to load too. You can see it happening in this video below.
The issue can be resolved by simply exiting the jukebox and restarting it, but it's odd to see a new glitch enter the game as a result of an unrelated update. Still, at least this one doesn't ruin your entire save file.