Frustrating this, isn't it?
The process is as follows:
1) Discover your audio codec. If it isn't listed in your PC specs then run Windows and check the Device manager to find it.
2) With that to hand check the AppleALC Wiki/FAQ to see if it is supported, and what the possible layout-IDs could be.
3) Install AppleALC.kext (along with Lilu.kext), declare in config.plist and add the first ID either to a DeviceProperties entry OR an alcid= boot-command in the NVRAM section of your config.plist.
4) Reboot, reset NVRAM from the OpenCore boot menu. Boot again and test audio.
5) Repeat until you find the correct ID.
OR
a) Install VoodooHDA.kext instead. Declare in config.plist.
b) Reboot.
One of these should work. If not pack up and go for some fresh air.