I just got a new 4GB card for my BookPort. I have noticed that navigating between folders has slowed down considerably from when I had a 2GB card. I used to be able to go from folder to folder almost instantly, now it takes three or four seconds to find the next folder. The situation is similar when going from file to file within folders. Is anyone else with a 4GB card having this problem, and is there anything I can do to speed things up? Thanks, Sarah