FabFilter

I was doing some reference checking and I noticed a discrepancy between ProQ3 and a couple of other stock EQs. This led me to have a look at the analyser when fed white noise. In this case the other stock plugins show a basically uniform response from 20Hz-20KHz whereas the ProQ3 shows a linear increase in level from -12dB at 20Hz to +6dB at 20KHz

What's going on????

Thanks :)