Vanishing & Re-Appearing ext drive. HELP!

[Paul Graham]

Im running mountain lion, With all updates on a 2007 iMac c2d with 2gb's ram.

My hard drive inventory is as follows -

MAC OS
Time machine ( Seagate 320gb ext )
Media 1 ( WD Elements 1tb ext )
Media 2 ( WD Elements 1tb ext )
Life studio ( Hitachi 500gb ext )

Media 2 is the issue.

One moment its there, then I get the message about not ejecting correctly ( I haven't ejected the drive )

I reboot with the drives unplugged, Then replug them in and its there again for a moment.

All of my ext drives are connected to two powered usb hubs. ( So theyre drawing power from the wall and not my mac )

If anyone has any ideas I'ld love to hear them please as this is infuriating me no end lol!

 

[enoC]

How does it react when its connected directly to your iMac?

 

[Paul Graham]

How does it react when its connected directly to your iMac?

Havent tried yet as I cant get behind my desk until tomorrow now.
But I will try it and I'm thinking about minimizing the amount of USB devices I
have plugged in.