I just bought a Neo Geo 4 slot arcade cab, but the mother board doesn't play some of the sound effects like firing, hitting, some of the instruments in the BGmusic, and the digitized voices. I plugged a friends mother board into my cab and it worked fine. Once I was playing metal slug x and the sound fx came back for about 5 seconds or so, then it left again and never came back since. I would much rather fix the mother board that I have than buy a new one. Has anyone had this problem occur. What could be causing it. Any help would be appreciated. Thanks in advance.