I have noticed that since I installed Parallels on my MBP the desktop wallpaper has a tendency to stop changing. I don't have any definite sequence of events that I can point to, but I have noticed that sometimes after I run Parallels to run some Windows app suddenly the photos that make up my screen saver/wallpaper stop changing and I have to go back into System Preferences -> Desktop & Screen Saver and recheck the Change picture and Random Order checkboxes. Sometimes I also have to reset the image size from Fill Screen to Fit to Screen. Has anyone else seen this? And is there some way to stop this from happening? I am new to the Mac and Parallels so perhaps this is an OS X issue, but I don't remember seeing it before I installed Parallels. Thanks for any help.