That… doesn’t really make any sense to me. Tinnitus is a ringing - call it a thin buzz, a whine, a whistle, but it’s a tone isn’t it? How could you not tell whether you were matching the pitch?
Because I can't actually hear that frequency. If I play sine waves through ear buds and increase the frequency, the highest pitch I can hear through the earphones is lower than the pitch I "hear" through the tinnitus.