Excessive soot on Bayou SP10?

Hey everyone,
I was just wondering if anyone else had any issues with soot while using an SP10. I have burned off the paint, played with the air mixture, and still cannot seem to get a blue flame regardless of valve setting. I am actually wondering if this is a defective burner, because I have not found that others have not really complained about this. 4 boils with this burner and for the record, this is A LOT of soot, not just a dusting. The bottom looks as if it was painted black.
Brew kettle is an 8 gallon stainless (not a turkey fryer). And the regulator is the 20psi version. Thanks everyone.

Side note: about to do first all grain batch: just made 10 gallon HD Rubbermaid MLT. This forum has been such an enormous help so thanks to everyone who posts on this site. It's a great group.

This is probably NOT the issue.. but worth a simple check. A few years ago, the water heater in my RV started putting out a lot of soot. The answer was not obvious to me until someone asked me if I had checked for spider webs. It seems there is a tiny spider that LOVES the smell of propane and builds a very finely meshed web inside the mixing chamber.. the area between the venturi an the burner itself. I'd first clean out that whole burner assembly as it seems something, whatever it may be, is not allowing enough air to be mixed with the propane to form a clean flame. You may never get a perfectly clean flame like you do on your home range.. but it should be pretty darn clean.. even if there are some orange tips to the flame.

If it has been doing it since you got it, more than likely it's defective.

Thanks for the responses. Amazon agreed to replace, even though I am outside the return window. Great company.