1997 Chevy Suburban CAR HORN

Noises problem
1997 Chevy Suburban V8 Two Wheel Drive Manual

for the past few months our car hron has been going off by itself. Whether we are driving or parked. Is this a fuse problem or a mechanic problem? Is it an easy repair or costly? We love our suburban and get really frustrated and embarassed when we are driving thru a parking lot & the horn all of a sudden goes off. Please help.