Propane burner woes

Everything was going well today with my bayou classic burner until I started my boil and needed to change out my propane tank    When I put on the new tank I couldn't get a good burn.  The gas barely came out.  In a panic I ran out and bought a new regulator and fitting to make it fit this stupid burner.  The new regulator did not do any better.  I took everything apart but there really isn't much to it.  The burner is fairly simple, it is just not getting enough gas.  Previously it burned with a loud noise and really put out the heat.  Are the blue rhino tanks crap?  As I slowly unscrewed the regulator I got a strong whoosh of gas so the tank is full.  I'm afraid my wort is wasted.  Anybody else experience this and can shed some light?  Thanks.