Bought a Cobalt S1000 10" a few months ago; everything was great. Now, all of a sudden, when I connect it to my Macbook with a USB cable and select its "Turn on USB storage" option, all seems to go smoothly on the table, but it doesn't seem to mount on my laptop (can't find it in disk utility either). There's a message on the tablet saying "Make sure you have unmounted ("ejected") your Android's SD card from your computer" before turning USB storage off, but I obviously can't do this since the computer doesn't recognize that it IS mounted in the first place. If I turn off USB storage anyway and disconnect the USB, it won't be recognized again even if I reconnect the USB (I have to restart the tablet to recognize again). I know there's a connection, because the battery charges and the USB storage screen pops up automatically. Please help! I absolutely can't live without this basic ability to pass files back and forth, it's the main reason I have the tablet.