Sustained use of Cinema display audio results in noise, choppy audio, then cutting out

Question

When I play a sustained audio stream through my 27" LED Cinema display – for example, listening to my music collection on iTunes – for a couple hours (since I powered on my computer), the audio suddenly gets very noisy and after a few seconds really choppy (+ noisy), and waiting another few seconds it's barely audible (just repeated hints of noise). After this happens, I can press Pause in iTunes, wait a few seconds, then press Play, and the audio is perfectly fine again.
Then, after only a half hour or less, the same thing happens, and I have to do the same thing to fix it. I am always able to fix the audio perfectly fine, but it inevitably craps out again after 5-30 minutes.
If I power off my computer or let it sleep overnight, then come back and play iTunes again, the audio will be fine for a few hours before this inevitably happens again.
I've followed the advice of an Apple support technician of resetting both my NVRAM and SMC, and that had no effect. The Cinema display audio continues to behave the same.
I have the USB for the Cinema display plugged directly into my MBP's USB port (no other USB hub in the way).
I have the latest version of OS X and thus the 27" Cinema Firmware 1.0 update has already been applied (I tried applying it by downloading the firmware update manually, but it refused, saying I do not need this update).
This should go without saying, but this never happens when I play music through my MBP's built-in speakers, or when I play music through external speakers plugged into the line-out port. It's behaviour that happens exclusively through the 27" Cinema display's audio interface.
Thoughts, anyone?
I'm especially curious whether anyone else has had precisely this kind of audio problem with their 27" Cinema display. I've seen many people post audio issues relating to their 27" Cinema display, but most of those problems were remedied by the 1.0 firmware update, and besides none of the problems were described quite like mine (specifically, audio that becomes noisy, then mostly cuts out - it never completely cuts out - and that can be reliably [temporarily] fixed by pausing and playing the audio again).

Answer 1

Can an MBP Sound preferences output to the display as opposed to through usb?  I use a mac pro and have those two choices for my mini-displayport 27" apple display. 
I am not suggesting this as a fix but only testing various other paths to try to diagnose the problem.
What first came to mind in your description was that you are having some kind of temperature problem.  And I think the temp problem lies with the MBP and not the display.  To that end you might consider adding one of the temp monitor utilities like iStat Pro, iStat Menus, Temperature Monitor, Temperature Monitor widget, Hardware Monitor, etc.  See if there some correlation with the temps shown in some of the readings and your sound problem.