Hope you get one. Did you ever find a caller or is it just you?
If you end up calling solo... my two cents is that they can pinpoint location from sound much better than we do. If you start to get in close, make a final stand of calls and then rush forward to set up 50+ yards ahead of where you last called and try to sit quietly. Hopefully they go to where they last heard you.
I find if I don't do this, they always hang up about 80-100 yards out (if they come at all).
Good luck, kill a monster!