Since launch, the app had a notice informing gamers that the songs were not being rated by ratings groups but now Nintendo will issue a new warning even before download that the game has mature content.
"It is however very important to us that all users of Wii Karaoke U by Joysound understand that some lyrics contained within songs may not be suitable for all audiences and as such we will immediately be implementing an additional message within the Nintendo eShop (prior to downloading the application and ticket purchase) as well as on the Wii Karaoke U by Joysound website pages," Nintendo added. "In the near future this message will also be incorporated within the notification that is displayed as the Wii Karaoke U by Joysound application is launched."