Hufty - thanks for the encouraging comments. I don't even want to get started on what the issue really is... I have theories, but I've been proven wrong so many times now...
I ordered an "Eardoc" a few weeks back, before I saw Mr Specialist. I have a strong suspicion it will find its way onto Ebay without having the packet opened...
The diagnosis treadmill is not a nice one for these kinds of conditions - ear function isn't a simple area of medicine
edit - before I get my hide tanned, I'd like to remark that no area is simple - it's just that inner-ear conditions can be particularly awkward to diagnose.