Recommendations, rubber/vibration coating for plastic parts?

I would like to paint a rubber or similar coating on some door and other interior pieces that are rattling with the new stereo install. Hard part seems to be adhering to plastic.

 

Check out butyl sealant tape, sound deadner and closed cell foam. I'm not sure to the areas you are referring but the above items as well as mass loaded vinyl is what I used for my audio overhaul. There are many installs on this forum which tipped me in that direction. You can get as thorough (crazy) as you want. It's time consuming but well worth it. For me, nothing vibrating.

 

I have been using Kilmat. My noise source is the door panel inset where the plastic piece the holds the window switch mates up. The edge of the window switch plate vibrates against the door panel. I am going to pop off tomorrow, and try to add a little Kilmat. I noticed the issue out driving. Thought about some type of rubber coat, spray on, that would be thin, yet dampen.