I have discovered that the culprit is a service called "Nahimic service". It's a part of my Asus motherboards Sonic Radar and Sonic Studio. When I disable the service the game works without issue, however when Nahimic service is running the Definitive Edition will CTD as stated in my OP.

I have tried updating my motherboards audio drivers from the Asus website but it's not fixed the CTD issue. The only things I could do are either uninstalling Sonic Radar and Sonic Studio, or disabling the Nahimic service, thought tbh this is something Larian needs to sort out with Asus/Nahimic to make the game compatible.

Last edited by ScenicGaming; 08/02/19 07:52 PM.