When I first read some of the posts on Craigslist about ASCAP muscling nightclubs for licensing fees from the performance of cover songs, I shrugged them off. It seems I shrugged too early. New City reports that Chicago area musicians who like to hit the open mics and jam sessions have had to do so incognito or under a cloak of secrecy due to ASCAP's crackdown. Back in July ASCAP filed 30 separate copyright infringement actions against a number of nightclubs. So far, no Chicago clubs on the list.