Super Neo Geo 29 MVS 2 slot sound problems

hi guys, i have a super neo geo machine that plays audio fine on a naomi and a cps2 but when i hook up my MVS 2 slot it doesn't sound all that great. if its really low it wont crackle but if i raise the volume up it starts getting really distorted and popping. when i put in the KOF cart it sounds like some of the audio is missing (just very low compared to the other audio) any help would be greatly appreciated.

Is it a bad KOF cart? I've come across lots that had issues with sound and video while other carts worked perfectly

thats a possibility. metal slug 4 is a brand new cart and i cant take the volume too high without it sounds like crap.

EDIT: wrong post

Also: http://wiki.arcadeotaku.com/w/Beginners_Guide_To_SNK_Neo_Geo_MVS#Running_MVS_in_your_JAMMA_cabinet

It sounds as though you're plugging in a 2-slot to a jamma harness. The 2,4,6, and (I believe) some 1 slots aren't exactly matched for a jamma pin out. Most notably, the audio pin outs I believe. Team_andromeda's link should explain it better than I can. I'm not at home, and using a tablet or I'd get you some links to help out as well. Hopefully it you can get it resolved!