Thanks for the advice chaps.
Went out tonight with ear plugs, wooly hat and balaclava, engine didn't sound so good but ears felt more protected, I think it was the long run on the motorway the other day, it was very hot so took of the wooly hat, ears were fully exposed I think that did the damage, no side doors also creates quite a draft.
Now looking for an Aviator/Traper style hat with fur lined ear flaps plus the earplugs may do the trick.