Plugin raises gain 3db?

[madlo]

Having a strange problem wherein adding a plugin, in this case eq3 1-band, adds 3db (roughly) gain to the signal. I am using the eq as a high pass filter, so the level shouldn't be getting higher with the plug instantiated. Any ideas as to why this might be happening?
System=
macbook pro i7 2.66 dual
Pro Tools 10.2
digi 003/eleven rack (interface doesn't change behavior)
Mac OS 10.7.4

I have tried trashing prefs, restarting numerous times, word clock vs internal
Any insight would be greatly appreciated. issue does not seem isolated to eq3 plugin, e.g. channel strip gives same results.
thanks!

[clausiii]

Everything´s ok! This is normal! Filters boost a bit at the point where you set the frequency. The more dB/oct you use, the more the filter boosts. Analog filters work also this way.