Loud Chime / Directional Sound

[jesusdima]

Hi

 

I bought a NBS Crew Cab Siverado with Bose and 6CD Changer

 

I recently purchased a navigation unit, everything works except that the door chime and the hazard sounds are very loud, is there a way i can turn this down? The dealer says that he cant turn down but i don't trust them because they dont know anything about the programming here in mexico

 

Thanks for your help