As per  


Amazon says that it is not an issue with ASAP, but rather a bug with the screen saver images.



We have confirmed this issue was not caused by ASAP. You’ve helped us find an edge case bug related to our screensaver – there is a small possibility if a customer uses the “mosaic” feature (not the default setting) on the screensaver images will not be cached. We’re working on a software update that will fix this bug, and in the meantime you can turn off the mosaic view for the screensaver to avoid the issue.