Fruit Machine Chat

The alarm on my magnificent 7's machine goes of when I get onto the feature board any ideas what's causing it??? Its doing my head in!!!!

Hi I am new to this and need help I have got a bar rest magnificent 7's machine. It works fine on free play but when playing with money the alarm goes of when you get on to the feature board and the display reads system stack alarm any ideas what's wrong your help would be really appreciate thanks i...