Awful results with external speaker

It seems to be useful for internal iMac speakers only. I tried to equalize the sound of KEF X300A speakers and it turned out to be a disaster. Waste of money for me. At the end the uninstalling script delivered an error so I am not even able to get rid of it.

Kraftsman1124 about Boom2:Volume Boost & Equalizer, v1.0.1