Hey @Stuart_Hudson,
Ben here with the support team, you have my sincerest apologies for the delayed response and for your wait. We’ve made some recent changes to the support team structure and some reports have experienced a longer response time than usual.
Since none of the above steps have helped you with your issue (thank you for all the help so far @Rugby) I’d like for you to try one last thing based on the information from this thread.
Specifically, If you’re comfortable editing the registry, try clearing out everything in HKCU/Software/Windows-SLS as well as resetting the physical_address key.
I will be monitoring this thread for your reply 