This is a problem I just recently started having. Whenever I plug in a usb cable to my phone, the sd card unmounts itself, in that order. If I plug in the cable and THEN insert my sd card, no problem. I've formatted my card on my PC, and also on my phone, and the setting to charge when plugged in and not to set as a disk drive is set. It seems however that the phone is ignoring that setting and mounting as a disk drive. Anyone else having this issue?