t4ere is somet4in9 wron9 wit4 my computer w4ere every once in a w4ile (suc4 as ri94t now) ill be typin9 and t4en i all of a sudden wont be able to use t4e two letters between f and i (w4ic4 is w4y im usin9 9 and 4) as well as t4e backspace key and t4e quotation mark key. t4en t4ey will all of a sudden become enabled a9ain. does anyone know w4y t4is mi94t be 4appenin9 and 4ow to fix it?