granth
+1y
depends on your laws really, but you would be suprised how loud things are with the windows down. dont know if you have turned yours up and walked away til you couldnt hear it. if its a smaller economy car then its even worse as nothing stays inside of them.
You can always go up to the police station and talk to him about it. More times than not cops will atleast listen to your side and possibly help you out. If you tell him you didn't think it would have been a problem half way up on the highway going the speed limit, he may take that all into consideration and atleast give you a break on the fine or something.