Its been a few weeks since I wrote anything here, but since my hearing therapy appointment I have been using the Opticon tinnitus sound app on my mobile phone. Using white noise mostly I have found that my perception of the level of my tinnitus is lowered, a relief. 6 weeks on listening to the distraction noise I am not cured, but may be distraction will reduce how I 'hear' the whistling sound. Time I guess will tell.
Tinnitus and Colon Cancer