more then anything i was disappointed that it started acting strange to him.  i have some allen drivers,  and i just used the proper allen bit , and turned the pots + / - a little , then back to its original position.  and screen returned to normal.  my bit kit is kinda like this kit here…  -- i love this kit.    http://www.microcenter.com/product/262434/33_pc_Screwdriver_with_Bits