I just purchased my first Android device - a Verizon Samsung Galaxy S3. With it, I purchased a new class 10 32gb SD card. I have copied some MP3 files from my Windows XP computer (via USB) to the SD card. At first, it was evident that the files were on the card and were recognized by the phone's media players. After a short while, however, the media players would fail to play the MP3s, stopping just a few seconds into the song. And eventually, the file would disappear altogether. My "lost.dir" is empty. I have not had problems, thus far, with the files that I copied directly to the phone's internal storage. Did I get a bad SD card? Any ideas? Please help! Thanks!