It could be everythings normal. I'd have no way of knowing.
The subs are in the front corners outside the M80's.
The Paradigm PS1200v4 is on the left half its width off the side wall half its depth of the rear wall.
Low Frequency Extension: 21Hz (DIN)
The Paradigm DSP3100 is on the right half its width off the side wall half its depth off the rear wall.
Low-Frequency Extension*24 Hz (DIN)
I do get some very nice lows from them but until I turned them down it wasn't quite right.
I'm tempted to turn the subs down to +/-25% on the back panels and adjust the AVR up a few db.
7'x 12'x 21' cave
3 Paradigm subs