It's puts me to sleep almost instantly...
Have you tried a somewhat longer WBTB period? Or have you been doing the WBTB at all? (I know you don't like to do WBTB.) Anyway, WBTB seems to be important in the SSILD method. If I don't do at least 10 minutes of it, I fall back asleep without making it through more than a couple of Cycles.
Or, maybe combine SSILD with a supplement that keeps you from falling asleep too soon?
...but it made me realize I have pretty bad tinnitus. I never noticed before.
It's a good sign that SSILD has caused you to notice that. It seems to be making you become more aware of things as you fall asleep.