I have a cheap storage device that has two 1 tb drives in it. I was trying to use one for iTunes and one for Time Machine. It's connected to my 2011 Mac Mini and if I let the computer sleep the drives unmount from my mac mini. The device is connected via usb. Of course Time Machine will not work when it unmount's and it is just a huge pain. I hate to buy a new external hdd when I have these two drives, but I can't live with this thing. I also have an Airport Extreme and tried using this as network attached storage, but I have the same problem. Do the Synology units have the same issue...? My box is a Sandisk... any info from owners of Synology would be much appreciated. Don't mean to hi-jack this thread...