I have been starting my sets with 2 invitational howls on my zepps 1080. No barks whatsoever, though I do on some put the little quiver in before going to the howl. I do 2 of them and wait a few minutes. Then go to predator calls for a few minutes, about every 2-3 minutes and waiting about that long in between. The sequences are usually 30 seconds or so at a time. After 3-4 of them I throw in a different invitational call from a separate howler, and then do another distress sequence or two. Finally, I finish with pup distress or kiyi's and wait about 2-3 minutes before leaving. This is in Southern WI, but with zero luck so far. Anything I should try or that I may be doing wrong?