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I have a Kingston DataTraveler 108, which is recognized by any computer I plug it into. When I try copying files to it on my MacBook, it is sometimes suddenly ejected.

I've had the same problem copying large files off of it. I have no problem when reading files on my MacBook, and I haven't had a problem opening files on other computers.

I'm running Mac OS X Lion 10.7.2. There are two USB ports and the problem happens on both. I've also tested with Windows on the same MacBook — with same problems.

The drive gets really hot when it's plugged into my MacBook. Is this a software or hardware problem, and is there a fix for it?


I've updated to 10.7.3 since posting this question. Also, my second USB drive of the same kind has started the same behavior. I think it's just the kind of USB drive... Can anyone offer a way to verify that it's the drive and not the port?

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Are any of the other computers also Macs? Does it happen on all USB ports of the MacBook or only one (or does the MacBook have only port anyway, don't remember)? – patrix Nov 14 '11 at 19:09
There are two ports, happens on both. Just tested on Windows and this MacBook. – Moshe Nov 14 '11 at 19:10
I had this issue before but using mulitple PC's. You will find that the USB is at fault, if I were you I would back it all up on another machine and get another USB, you can get an 8gb version for under £10 – Graeme Hutchison Nov 15 '11 at 14:10

If it happens to your drive only with your macbook (on both OS X and Windows) and works fine with other machines, then the problem is most likely your USB port.

I suspect that it is supplying more than the stipulated voltage (5V ± 5% for USB 2.0) and your device must not be sophisticated enough to only take what it needs.

You can check this using a multimeter and a USB male connector (I chopped a spare USB extension cord when I needed it). It should register the correct voltage and if not, there's your problem.

If you're going the chopping an extension cord route like me, here is what it will look like if you strip the wires (image source)

enter image description here

The white and green wires are for data transfer — you don't want that. The red is +5V and the black is ground. Connect your multimeter to those to check the voltage.

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I can confirm the warming of USB drives on both of my macs. Drives from various manufacturers.

The sudden ejection appeared to when reading old CF cards in a card reader. For me it only happened when having several file accesses at the same time. Seems to me like hardware limitations of the cards - but who knows...

Now I disable spotlight and the trash on my thumb drives using this suggestions. And the warming of drives seems "reduced".

So - it looks to me chances are your drives are old but good. But you should keep backups anyway :)

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