S01E02 might have had audio that was out of sync, missing, or in a format (like DTS) that caused playback issues for a large number of users. The "PROPER" version provides a fixed copy that is "DTS FREE" for better hardware compatibility.

Classism, corporate greed, and human connection in a digital age Available On Amazon Prime Video murder mystery clues revealed in later episodes of the first season?

Sounding Out the Digital Afterlife: Getting DTS Audio for Upload S01E02