The response I got back from MacEffects was that the issue is most likely due to issues with the sound chip at UB10. I checked that area with a 30x loupe and did not see any corrosion. They offered me a replacement accelerator or a refund, but I think it is something with the logic board at this point. If I power up the Mac LC II and the power it off an on again the sound is Ok. I can do any number of power cycles in succession after that and the sound is fine. Let it sit for 5 minutes and the issue comes back. I am just going to keep the accelerator and dig a little deeper with LC II logic board.