What would really be nice to see is a response graph of your sub via REW (see the
REW Forum for more info if you are not familiar with it). That would give us a clear picture of what you are hearing. Turn all equalization off on the receiver (turn Audyssey off). Run the Auto-Setup only on your Onkyo with your SVS gain set at about 12 o'clock. Do not run the Audyssey EQ. After you get the Auto-Setup finished, then take a response measurement sweep with REW and post the response graph here. Let's see what it looks like with the sub located in the corner.