This would explain why I had in what I thought was the wrong tone and was missing a lot so I set it to no tone. I monitor the area on visits to my family and noticed that discrepancy on my last visit. Gives me something to check into if I can recall my "contacts"
They do transmit from at least 2 different towers, so that sounds like a good guess. As I am using 91.5 in my scanners, I was unaware of the DCS. I'll have to add it and listen more.
Word is that Washington County will eventually switch to the DCS system in order to solve an out-of-state interference problem. The process will take some time because it costs money.