Seems difficult to prove where the sound came from. Couldn’t one contest it and say “that wasn’t my car, it was a different vehicle making the violating noise”?

Seems difficult to prove where the sound came from. Couldn’t one contest it and say “that wasn’t my car, it was a different vehicle making the violating noise”? Unless you’re the only vehicle on the road it seems more difficult to prove than, say, red light cameras.