Hello, I just received my jxd s7800b and i have it hooked up via usb to my pc running windows 7. for some reason windows 7 detects the s7800b but i can not access it as a storage device to add stuff to the microsd card. I have activated mass storage, has anyone else had this issue? i've plugged in other storage devices (usb flash drives) and it works. just cant access the sd card from the jxd7800