If the bike is otherwise running smoothly, you probably don’t have a vacuum leak. Assuming no other leaks, you could try an experiment. The F/L switch is 4% throttle in the stock tune. If you set it to zero, the main F tables will be used down to 0% throttle. Decel pop is at 0% throttle. Popping on my RIII occurred between about 2000 and 4500 rpm. So trim up (as a percent) the F fuel values in the 0% TP column starting at +10% at 2000 (don’t want to interfere with the idle) to 15% at 4500. Add more if it still pops. This is what is commonly done with Power Commanders. Potential problems are that you may lose some smoothness in the throttle up to 4% and the O2 sensor could lean out what you added. Does the DNK tune change the F/L switch? I’d like to see what she did if someone wants to send it. I don’t have a Rocket so I wouldn’t be using it.