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You could install a remote control relay to connect or disconnect the speaker. This way you could choose to turn it on or off as you wish. Basically becomes a mute function. Since you need to have your phone with you to drive a Tesla, get one that allows you to control the switch via the phone. Something like this would work well. https://www.amazon.ca/DSD-TECH-Bluetooth-Control-Compatible/dp/B07CZF154L