Subliminal Talk

I've used the 20-20khz frequency test and I get very slight, almost unnoticeable static when it's close to the end. I want to know if this is 20khz, or if it only comes close:

Bumping for an answer.

Well, I don't know about your test volume, but I have got a much higher amplitude at the whole frequency range.

Mine looks like this when listening to a normal sub:

how do i test?