I am going to answer this one myself. I did a google search(much better than Bing) and came across several threads with similar issues, not the same but similar, the advice given was re-install realtek drivers, of course update if there are newer ones available but as mine were already the latest I just re-installed. To my surprise it worked. I suspect there was a setting set to off or something not loading that the re-install put to rights. Anyway all is good fo me except for my Bose BT but I can live with and to be fair not a Dell issue.