Even a towel. I believe there's an anti-rattle idea thread somewhere on RV.net
Personally, we don't try to suppress noises that mean we're goin' campin'. Noises that mean something's wrong, yes. Pots'n'pans? Nope. They remind us we're fortunate to be on the road to relaxation and adventure.
Only loosely related to your stove, you can notch a paint stir stick to drop behind the three burner knobs. It's easy to bump a knob and have it turn to an ON position. Paint stick prevents knobs from being pressed far enough to also turn.