Pressing on the lower 2/3 of the trackpad will always make it click, whether or not tap-to-click is enabled. That is normal. It's the same thing as a mouse click. If you don't want to click, don't press.
I actually meant this as a hardware issue, rather than a software issue. The Button itself seems to click but it does not click on the screen. If I just smoothly roll my hand over the trackpad, there is a slight sound.