E-Brake Release Button Rattle

[Banditorama]

I have a 1929 with the push button style emergency brake lever. Not too long ago, the button itself on top developed a rattle while driving down the road. The button itself feels loose. If you gently rest your thumb on it, the rattle goes away. Any tips on how to fix the issue?

This is a new issue, I've hunted down almost all the other squeaks, squeals, and rattles on this thing. I cannot stand the sound of a rattling car and I'm getting sick of driving with my thumb resting on the button all day