Ok...so..you have what I consider to be the number one issue with calling. Thin or forward pressure air. Using this kind of air does two things, first it raises the pitch of the call and makes the call sound thin (thin meaning very little rattle).
Now...place your hand in front of your mouth and pretend to blow a call and do a single quack. Feel the temperature of the air hitting your hand. Next use the word hut (like a quarterback) and feel the temperature of that air. Lastly, do the quarterback back hut again but also drop your adams apple. You will find the last method will produce the hottest air.
Take that quaterback hut and dropped adams apple and blow a single quack into the call. You should hear a deeper tone and feel the reed rattle as you quack.
Just do that. Once you understand and feel the differance we can talk about qating of the note.
By the way....again hats off to you for posting a file. I'll do all o can to help. Better caller equals better call maker
Stump