So the ear appears to be a persistent problem - I don't want anything done though until I get my new obturator and see if that helps. In the meantime though I have found a way of draining my ear.
I go to Karate twice a week with my son - we train for an hour, then I usually stay on for a further hour to do bag work (punching bags, as opposed to punching thin air).
I have found that by the end of the session - my ear gurgles (only I hear this) and empties - I can hear clear again. This then lasts for a few days.
I can't work out if it is the head jarring that occurs from punching the living daylights out of a bag or if it is the workout I get that opens up all my blood vessels and tubes in my ear through body heat and the blood pumping around?
Whatever, it works, and it makes it more bearable.
I'll see how I get on after my definitive obturator is made - if i still have problems after a few months of having it, I will seek out something more permanent, perhaps grommets.