27" iMac 2nd display problems

[gbarlow]

Alright, so as the title suggest I'm having some issues with the second display for my iMac.

I'm running a 27" i7 Imac with the 24" Apple Cinema Display as the second monitor. I have it connected via the mini display port and also have the USB connected as I am using all of the available usb ports on the display as well.

The problem:
From time to time the cinema display goes completely black, the screen is still active as the windows on that side of the screen continue to function and the usb devices connected to the display still work but no image is shown. In order to fix this all I ever have to do is eject all the usb devices and then unplug / replug the display and everything returns to normal. It's not a huge issue but it is becoming a little annoying. Today it took three tries of replugging it to get the display to stay powered.

Any thoughts on what might be causing this to happen?

 

[Warbitrary]

If you put the Mac to sleep and wake it up, does the screen turn back on?
If you don't plug the display's USB port into the iMac, does the problem go away?

 

[gbarlow]

If you put the Mac to sleep and wake it up, does the screen turn back on?
If you don't plug the display's USB port into the iMac, does the problem go away?

Putting the computer to sleep and re-waking does not solve the problem and since it is a random occurrence and not something I've been able to force happen I have not yet been able to test it without the usb plugged in.