I've had tinnitus for years now and it never goes away. Sometimes the 'ringing' is quiet, but most of the time it's very loud and annoying. Mine actually sounds like cicaidas, not ringing, only unlike the bugs, it doesn't stop when it gets cold outside.
That’s what mine sounds like too. It is always there but if I don’t think about it, it stops bothering me for long periods of time.
You might want to try this software, it helps me.
http://www.arteson.com/audionoise/index.html