You're not experiencing anything others don't have problems with. If I had to guess, I'd same that's the most common problem with coyotes.
In my opinion, there is no magic secrete or sound. Try to get in the woods. Don't try to call them into the open. Stay patient, "wait them out ". Often times they will come in after you're done calling to investigate.
There is a great article in this months Predator Extreme dealing with just this issue. I recommend getting a copy and reading it.