So I got an 8BitDo SN30 Pro controller recently. This is one of my favorite controllers I purchased for the Switch; great to use with Steam as well. Unfortunately it had noise issues. The vibration shook and rattled the buttons. And the buttons themselves had a plastic click when moving back upwards.
I decided to fix the noise with some Liquid Electrical tape I had. This process can be used for most noisy controllers. Just be sure to not use too much tape around the areas where friction would prevent the button from moving up and down.
I’ve posted a teardown of this controller to Imgur.
Hope this simple project can help someone!