is it a buzzing from the back of the car. it is probably a fuel pump in that case. nuthin to worry about. If your buzzing is coming from under your dash or up by your seat somewhere it is a faulty warning buzzer. If this is the case you will either need to find the buzzer under your dash and disconnect or replace it. If you cannot find it you can ask a local mechanic to do it for you, or you can get a "Haynes" manual or other manual specifically for your car, and that will tell you where to find it.
To stop the buzzing sound you will need to disconnect the buzzer. It is normally red plastic and located near the steering column at the top of the brake pedal mount.
turn it off!
Where is the noise coming from? Under then hood, or interior?
top stops working. you stop hearing the buzzing sound of the switch working.
I am guessing that you have a bad turn signal relay. Locate it by sound and replace it.
I'm not positive this is the same for a 2010 truck as it is for the older ones but listen to the buzz and follow it's sound, a small buzzer should be located on the cabin fuse panel, remove this and the buzzer will stop, sometimes you can feel it vibrating to know which item it is.
A buzzing sound coming from a light switch means the switch is going bad and is shorting in the wall. Stop using the switch and replace immediately, this is a fire hazard.
To stop the buzzing of a doorbell transformer, you can try tightening any loose connections, replacing the transformer, or installing a noise filter.
To stop buzzing on your guitar, you can adjust the action of the strings, check for any loose frets, and ensure that the neck is properly aligned. If the buzzing persists, you may need to have your guitar professionally set up or repaired.
Don't go over 75 MPH.
Close the door
Update. This might be the answer. see:http://www.micra.org.uk/showthread.php?t=8953&highlight=buzzing