Just to chime in my experience. The ACRN tool at generalfuzz.net/acrn/ somewhat worked for me. My tinnitus volume is the same but the frequency changed. My constant tinnitus sound like an "eeeeee" all the time but after playing it at 4000Hz (it doesn't work for other frequencies), it changed it to a "sshhhh" static sound. I tried this in a quiet room, with windows and doors all closed at the early morning hours.
However, this effect gets broken with any moderate noise. Whenever I open the window which lets in a lot of background noise, the "shhhh" static sound resets back to a high pitched "eeeee". Replayed the sequence tone in a quiet room, it changed it back into a static "shhhh". Another note is that it resets back to an "eeee" sound after awhile even with no interruption. So it is temporary and I'll have to replay the sequence tone again to change it back to "shhhh" static sound.
Hell, I'll take a static shhhh than a high pitched eeee. It's much more tolerable for me. I just wished it doesn't reset so easily! I'm actually kind of blown away by this.
I just hope my head doesn't acclimate like it does with sound maskers. Sound maskers doesn't work after awhile.
Note: You really gotta find the correctly frequency. I tried 3000Hz, 3500Hz, 4500Hz, 5000Hz, 6000Hz, and etc, and it didn't work. Only 4000Hz works for me...