I had that for about six months
after some muppet decided it was fun to stick a vuvuzela in my ear.
all day long beeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeep drove me nuts.
but suddenly it was gone, really strange,
went to hospital for it and they said it was because of a overloaded ear nerve.
didn't knew this could happen from sunburn actually :wacko:
It can happen if you get an ear infection out of a simple virus. Usually it gets treated with medications that improve bloodflow so the damaged nerve can restore itself easier. Atleast that's how it went for me.