I'm using the latest MacBook Pro 13". I have a 320GB WD Passport External hard drive (Micro USB) which I use as my Time Machine backup. The problem I'm having is that this hard drive ONLY works when connected to my MacBook Pro directly, if I connect it to a USB hub it doesn't show up. I've tried this in 3 different hubs. All powered. Most times it makes a clicking sound and other times I get an error saying this "this USB device is drawing too much power...". The same 3 hubs work when I connect my iPhones, ipads and USB memory sticks, it's just that my WD Passport hard drives refuse to work through a hub. Even my WD Elements (Mini USB) hard drive won't work through the USB hub. Does anyone else have this same problem or any solution? I would be highly grateful. Thanks.