Bob, what I meant is that sometimes things happen, it's part of life. A few people suggested for you to check the drivers to take the speakers out of the equation but I didn't see a reply that you did, it might be something wrong with them or not, but worth to have a look.
I think by now, people understand that your equipment is the same and that your Onkyo had no problem driving your Polks for 20 years. These are not the Polks and I think any suggestion to determine where the problem is, is a good suggestion, it might be that the Onkyo dose NOT like the 4 ohms load or it might be the speaker, who knows?.
I, myself had a bad driver on one of my QS8s, I called Axiom, they sent me a new driver right away. Like I said, things happen. Now, if you want to look elsewhere is up to you, Axiom will give you a full refund..
