Windows 7: Win7 Slideshow desktop background flickers on change

My husband has an ATI Radeon HD 5800 Series graphics card and 3 screens set up on his computer. He has the included windows 7 slideshow for his desktop background. The pictures are pulled from a folder on his desktop and it holds 79 images currently.

Our issue is that every time the background image changes, the entire screen (all three as one) flickers a couple of times. While this does not seem to impact much of anything it certainly is slightly annoying, especially as he has invested so much time and money into making his "dream machine" desktop pc. Any suggestions as to why this happens?

I appreciate any help you give. I would love to be able to fix this for him.



Thanks!
Pam

**Edit**
Also, graphics drivers are all up to date as is windows. He is running 64 bit windows and catalyst control center (updated regularly).