Today I was driving about 30 mph in the right lane happily listing to Slacker when the car beside me in the left lane (almost parallel) suddenly began turning into my lane. There was traffic behind both of us so a panic stop would probably resulted in a rear end collision. Anyhow I mashed HARD on the horn while braking and he suddenly jerked back into his lane. We didn't touch but I'm sure we came within 2 inches. I masked down on the horn a good three seconds until he was back in his lane and I was well behind him. As the adrenalin began to abate I noticed how quiet it was. Slacker Radio had paused. Interesting. Either this is a safety feature (hold horn down for several seconds usually means something bad going down so muting could be helpful) or I somehow gripped the wheel such that I clicked the left scroll wheel. Who knows and I don't encourage others to try it.... so perhaps I'll just put it down to enjoying the idea that Tesla thought to include this safety feature: quiet after panic.