trouble printing

Help! my geo DK20S is clicking on and off by its self??? --- have searched online but havent found anything on this exact issue

Also check out the video's below!) It seems that one of the most common problems new screen printers run into is printing white ink. I’ve heard a lot of questions like: Why do all my other colors print fine and white is so tough? Why is it that my white ink is so thick? Why can’t I get a smooth...