Can't really help you on the horn issue, but your not alone. One day while driving i was sitting at a red light, and then the light proceeds to turn green. I start to accelerate and as soon as i hit about 5 mph my horn started going off. The funny thing is, the faster i went the quicker the horn beeped. When i hit about 40 mph it was beeping so fast, theirs no way in hell i could even try to manipulate it by hitting the horn button. I pulled over and popped the horn fuse and drove the car home. One week later popped the fuse back in, and it started doing the same thing. I took out the fuse and put it back in about 3 months later, and all is fine and its been going on a good 2 years.