Been there, Done that
Went through the same thing with my town, only it was becasue we were training dogs on my (10 acres) of property. They used to have an ordinance that specified a particular sound level, and times of day....but not anymore. If they have a complaint, they can charge you. They never even cameover to see what were doing(there were 2 police officers training with us) just sent me a summons in the mail, for multiple charges. We were trainingin the middle of the day, and nearest neighbor was 200 yrds from where we were.
When I went to court(with a lawyer) I took with me sound readings, from various noise sources that are daily around here (normalroad traffic, NG helicopters, airliners and a train that come nearby 2-3 times a day) ALL of which were considerable louder than a dog barkingat a distance of 50 ft.
Judge said it didn't matter 'cause readings were taken on adifferent day than the one I was charged on.
In short, I've been effectively banned from training dogson on MY property (which was purchased, just because it perfect set up, and in an area where no one would likely complain.)
Final tally, most charges dropped, fined $50 under "barking dog statute", but spent $3000 on legal fees.