Welcome to the board, trapper. I'm assuming from your topic, you are from Ill. If so, where abouts?
Also, by now, there's been a ton of guys out after these dogs. From truck hunters (drive around and shoot at anything that looks like a coyote), to snowmobilers and 4x4 atv's, to good callers and bad callers. So, in effect, many surviving coyotes are pretty wise at this time of year. That may be one problem.
I know some of the new callers are not patient and get up after a few minutes, disappointed that nothing came in. Needless to say, that's not too good, except for the dogs.
As far as what has worked for us here in NW ILL., is run the tape constantly, try to move the speaker to cover more than one direction( not 360 but at least 180 degrees) and try to call cross wind if possible.
The last rule is...there are no rules when it comes to hunting these dogs. I've had them come from all directions, especially the one you aren't looking. Camo up, sit in cover as much as possible, move as little as possible, and try to set up wisely.
Hope this helps a little. Also, the last couple of weekends, the wind here has been 25-35+. We haven't done much good then.
Good luck.
Terry