XRAY - Model racing cars

You may also have the expo or punch set to high, this will cause excessive buzz.

Thanks for all the good advice. The spring putting too much load on the sevo makes sense. I will remove the spring to see if the buzzing stops then cut the spring down a bit. I use a radio with a failsafe, and I've used rubber bands in the past, but it just seems wrong to put a rubber band on an absolutely gorgeous truggy

i wouldn't recommend cutting the spring down, i did this and ended up putting shims back in as it does not put enough pressure on the slider at neutral and makes your revs hang off throttle.

My friends E.C had your problem and it turned out to be the plastic rod holder that attaches to the horn. For some strange reason over time it starts to bind up, pull it and see.His servo was really hot and wore his batts down real quick. This happened to mine 2 weeks later! Just get a drill bit and ream it out slightly, problem solved.

Well I got it to the point where the buzzing at neutral is minimal and will even stop for awhile. I tried using a weaker spring which took load off the servo, but wasn't sufficient to close off the carb to 1mm. I also reamed out the rod holder, as there were some burrs on the rod itself.
I suppose some load on the servo won't kill it as the EPA are way down but enough for full throttle and lots of braking power. When you think about it the servos probably get loaded up and buzz pretty good through the course of a race, you just can't hear it!
Once again thanks to all who helped