Sli/ Audigy 2 Issues

I've recently built a new computer with a p5n-32 sli premium motherboard with 2 8800gt's in sli. I did have my Audigy 2 platinum pro card in use but took it out because of the squeal of death when using sli.Before I took it out I used it a bit when playing COD 4 with just one card being used (no sli) and it worked fine most of the time but it did do the SOD 2 times that I can remember. Now the IRQ's for the sound and video cards were the same but as for the IRQ for my onboard sound ( what I'm using for now), I don't know since I'm not at that computer and I haven't had this problem yet with it. I would just assume that it was because of the sli but since it has happend in a non-sli situation, I know better. Any Ideas or any body else experiencing this?