Anime News Network is reporting that Sentai Filmworks is recalling the Kids on the Slope Blu-ray collection. The set was scheduled to be shipped on May 7, 2013.

According to online retailer Right Stuf, the cause of the recall is that during the 11th episode, the Japanese language track features only mono audio.

Right Stuf says it has put a hold on shipping the release, but that some copies were shipped to customers before Right Stuf received the notice of the recall. Right Stuf has put a form on the company’s website for customers who have already received the set with instructions on how to return the disc. Right Stuf will ship out copies of the corrected disc when they are made available.

Source: ANN