I have had a software update for the DAB and at first it did not seem to have made any difference. However, I was sat in the car waiting for the missus and was messing about and pressed and held the Ensemble Learn. I noticed that it took about 20-30 seconds to complete to 100% and after that the DAB has been a lot better - not perfect but better. Previously just a short push on the Ensemble Learn button and the process was completed within a few seconds - but holding it down produced the results.
I am assuming that this process probably activated the software update somehow..???