it could mean you have a reactive component ? (tinnitus reacting to specific sounds). mine is (sometimes) dead quiet in dead quiet rooms and it is blaringly loud when triggering sounds are present.
Perhaps because yours is reactive that everything you hear is causing the sound to appear louder which is why it's quieter with ear plugs in. In a soundproof room there's no external sound for your Tinnitus to react to. That could be your answer. You just have reactive Tinnitus that can improve in time.
@jimvee yes it was continuously low in that room, and I had a similar experience before at a different test. I can hear it, but its only like 2-3 db's higher than my base hearing level.
I recall the first day or so after onset of T it wasn't really that loud, I could sleep through it. Then it became loud that I heard it over everything. I always have a fan on, there is always noise somewhere. Now however the fan triggers it but not as severely as it first did. It was everything my voice, plates, road noise, fans, running water.
@kingsfan Fortunately it seems it has a limit as to how high it will go, but yeah. The light droning sounds actually make it seem more present than a louder one, but I assume the loud one is masking it a bit.
Actually I get that drone sometimes... but mostly higher pitch. 8khz is what I was told, but it seems higher. Fans are something that aggravates it. I don't have much luck with white noise atleast that i have found. Sorry if I confused that.