Q: Background image disappears when I switch between user profiles

I have a Macbook Pro with Retina Display 15" (16GB Ram, 2.6GHz i7, 256 GB HDD, Mountain Lion 10.8.2) that I purchased in September 2012, and I have two active profiles on it: one for me, and one for my husband. Each profile is associated with a different Apple ID, & I originally set different desktop background images to each profile.

I noticed very quickly that when we switch from 1 profile to the other (by clicking on the respective name in the top right hand corner of the screen), the background image disappears upon login and I'm left with a plain blue background. Sometimes it will disappear from 1 profile, then it take 1 or 2 more switches backand forth, then it will disappear from the other. I'll reset the background image within system preferences, but after 1-2 more switches between profiles, I'm back to the blue screen. We like having the seperate profiles as we both have iPhones, and have the laptop setup with our respective iCloud and Mail accounts and don't want to use just one profile (which would it seems, fix the issue). Any ideas on how to stop this from happening? Obviously, I can reset it within system preferences each time, but it's a pain and I would like our respective background images to remain as they should. Any ideas?