Have folder of 500+ Jpg pictures. when in Library module and scrolling thru pictures using scroll wheel, The pictures are pix-ul-lated, as expected. then the system freezes and the screen goes white. Like the buffer is empty, or waiting to refresh. Is there a option to increase the buffer size? Or could it be thumb nails are being rebuilt? pictures are in a 2014 folder. Could it be the Hard drive? I see in catalog settings, the Smart Preview is at 1MB. is this when the thumb nails are kept. Just trying to improve my work flow experience.