AFAIK most noise ordinances are town or county level.
If you're being an arsehole you'll get pulled over. If the cop is bored he'll try to search you. There is virtually nothing you can do to avoid being searched if they really want to search you. They can say they smelled drugs, they saw you throw something under the seat, or even bring a dog and say the dog smelled drugs (not like the dog will take the witness stand to say whether he did or didn't)... none of these PC excuses can you really disprove in court.
Don't be an arsehole and don't break the law or have illegal stuff in your car and this becomes far less of a concern. Oddly enough it's rarely people that are actually loud who seem to have this sort of trouble.
OH and if you're routinely dealing with police this video should be informative and helpful with ideas of how to handle the situation.
https://www.youtube.com/watch?v=QR465HoCWFQ