I am trying to figure out why I am not hearing anything on the rrequencies used by some of the small city and township police and fire departments in Genesee County. These include Davison City and Township police and fire as well as Burton, Clio, Flushing, Richfield Township and others. I am using a GRE-500 and I have created talkgroups using the tower frequencies for Genesee County listed here on RadioReference.com. and the talkgroup numbers found here. I am hearing all sorts of other traffic on the MPSCS system in Genesee County, just nothing from the small units I listed. They are shown as being proprietary and I am not sure if that means some of the settings on the scanner for these talkgroups need to be different than a normal talkgroup setup. Any advice anyone can give me will certainly be appreciated.