Thanks for the info JoeAverage
It solved the audio problem, which is great. However, it's created an issue with database versions.
I use MySQL to 'synchronise' my media throughout the house with my 'main' machine been my PC (Windows 10). My PC uses Matrix 19.4 and MyVideos119 (database version) but after updating the NUC to the latest nightly build that has migrated to MyVideos 120, which means they are no longer synchronised.
Is there a way to fix this at all, is there a previous 'nightly' build that may fix the audio, without updating the database version? I'll check on this from a KODI wWindows side as well.
Thanks