Well, I thought I was good but audio keeps dropping off.
I thought it may have been an issue with VoodooHDA so swapped to AppleALC and injected 23 as others have.
I didn't realise I still needed to probe it with a linux live usb so booted into that and Mojave was fine. This lasted a couple of reboots then dropped out again. Rather than mess with my config, I tried Ubuntu 18.04 live usb but it's not coming back.
I had removed CodecCommander incase that was messing with it (and saw
avatecer wasn't using it).
Also tried the AFGlowPowerState and ResetHDA options with no luck (turned them back off afterward).
Code:
<key>Audio</key>
<dict>
<key>AFGLowPowerState</key>
<false/>
<key>Inject</key>
<integer>23</integer>
<key>ResetHDA</key>
<false/>
I've attached IOReg and Audio details from when it was last working.