Thanks for the suggestions. I agree that it would be wise to isolate my HT system, especially since I live in the mountains where the power is not always stable. However, I've used the 950 for many years now and I never had the crackling noise. It showed up about the same time that the optical inputs started failing, so I'm thinking it could be part of the same issue (bad circuit or solder joint). Regardless, I will most certainly need to send it in for servicing.