Assuming you have the isolated cowls and cowl mounted lites, next time
you have the cowl off spray silicon on the baffle sealing surfaces to
minimize the stick-slip excitation from the engine torsional vibration.

I also added a shock mount system to the landing lite housing when I
first tried the above, but that is not an approved mod. Something
worked though as I have not had a landing lite go in years on my 172M.