Files Deleted When USB Mode is Changed to Media

[sayus2884]

Hi, I'm using my SD card to store all of my media files and that includes the songs from spotify. However, whenever I connect to my PC to get some stuff in my SD card, the downloaded songs somehow disappears and I'd have to download the songs again.

It's annoying because my data is capped to 800mb per day and I use my wifi for work. Is this a crappy feature to protect the media files or a crappy bug?