Boost issues

[Tsi]

I really don't know whats going on with the boost controller, but I've had the knob in all the way and out all the way, and the boost just climbs everytime to 20+ psi. (I usually let off when it gets that high) Could it be boost creep, I just have downpipe and a cat hooked up right now and the downpipe isn't all the way bolted on. The boost controller can't be bad already its a month old, and it worked fine holding 18psi before, which way do u turn the knob for less and which way for more?? I have been hand tightening it, does it have to be wrench tightened in order for it to work right?? Maybe someone could enlightin me