What is the crossover set at ?
In my limited experience ,auto eq's tend to set the crossover far too high.(80hz is your starting point)
What size is your room?
Someone on here will suggest whether that sub is suitable.
I had a similar problem with a cheap paradigm sub.
Not enough power,therefore i had to choose between
Hardly hearing it at all or it being a bit out of control and distorting.....
Id imagine a small sub in a large room would present the same problem's.
You could also try putting on something with a repetitive bass
Track and walking about the room,if it's better in some places.....it may be ,you just need To fine tune the sub's position.
Sent from my HTC Vision using Tapatalk 2