2005 chevy cobalt ls door chime noise when i drive?

[dropdead_averageguy]

hi we have a new chevy cobalt 2005 it has 15,000km sometimes when we drive it we hear a chime ,like a door chime when you leave youre door open, but except we are driving down the road when it happens, any ideas?? also there is no indication light on the sound just appears please help