Long shot, but a 2008 would have time by now to get some crud on the burner slots, reducing the flame.
There is a procedure for cleaning that and clear the slots. At some point, the chimney above the slots gets big flakes of soot that keep dropping down across the slots and you get an "F" on the dial. Then you have to go in there and clear the big flakes out of the way and bang on the chimney to get any loose ones down before you put it all back together.
You might be at the point where the slots are getting plogged up, but not so badly yet that you get the dreaded "F"
