Thank you for the info Martin.
On Macs, the VirtualBox 5.1.22 audio options are:
- Null Audio driver
- Core Audio
Obviously, I have chosen Core Audio
The Sound Cards are:
- Intel Audio HD
- ICH AC97
- SoundBlaster 16
I have installed the Uniaud drivers from the netlabs site as per the instructions in the wiki page you linked to (v20170403).
I then switched to Intel Audio HD in the guest settings. No joy.
However, I then switched to the ICH AC97 sound card and I have sound. But the sound is slightly stuttering - I'm not sure if that is a known bug or something specific to my system. I wonder whether it could it be due to the fact that I picked SoundBlaster16 PnP in the ArcaOS installer initially and there is some fragment of that left in my config.sys that is causing a problem.
Still, progress! Many thanks