Same here as well. My AN, (aka Jusitn Bieber,named by my daughter because he is really annoying and we just want him to go away), was asymptomatic, but found on an MRI as followup for the optic glioma (I have NF-1). I would get an occasional ringing in my ear that would last about 10 - 15 seconds but never though anything of it. Now I know I can thank "the Bieber" for the noise.
Last Thursday I had my first real dizzy spell, and since then, the buzzing in my ear, and the fullness has been going on almost non-stop. I went to the ENT on Monday, and he prescribed a Medrol dose pak. I have two more days after today, and still no real relief. Tried Mucinex and Sudafed, but it hasn't really helped.