Weird CS4 Photoshop selection problem
I have what I hope will turn out to be a simple problem. When I use any selection tool (Lasso and Quick Selection first displayed the problem) if I add to a selection, a random, non-selected rectangle appears within my selection. So if I select the top 25% or so of the frame, it's all OK. If I add another little bit to the bottom, then I end up with the weird rectangle. The more I add, then I get 2 or 3 more boxes in there. Really frustrating to try and actually work with it. Any ideas?
PS- Only happening on my Penryn MBP 2.4 4GB 10.5.5- the Mini 1.83, 4GB is doing fine. Thanks in advance.