One work-around for this issue is to find your device ID within AppleACD97Audio.kext and place it in another audio kext to allow the system to recognize the device but not use the parts of the kext that was not performing well with your system.

NOTE: this is a sort of last resort type of procedure and I don't recommend using this right away unless all other options have been tried and tested and then failed you. This is what I did to enable my built-in Ethernet port to work... (I realize you might look at this and do a double take... yes ethernet... follow the same procedures except replace audio in for ethernet) I found my devID and placed it in the old (and I do mean very very old) forcedeth-v kext that was used in the past. I took out all devIDs from the section you find them in and replaced them with mine. For you I would suggest placing it in AppleOnboardAudio.kext and leaving the other devIDs.

Maybe this kind of procedure only worked for me because I got lucky in this instance... but I'm still using the kext to this day for my built-in ethernet.

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