Hi, I too have the same trouble. I am using a Dell Dimension 1100 machine, had iDeneb 1.3 OS 10.5.5 installed with everything working great. needed to upgrade os to get itunes and safari updates. installed OSX 10.6.0 by Hazzard. all went well except for the sound. I have the AppleAC97audio.kext installed that you posted and still nothing. the volume control displays next to the clock, but no sound. in the midi setup I can get channel 3 and 6 to make the speakers play static!