I was like this when i was younger. Listen to the reply above it's a good one. I can see as you get older these interactions do tend to get more pleasant.

Stop expecting the worse and remember the voice on the other end is a person like you. Also being polite and helpful without being demanding has made these calls much less of a runaround for me. Of course there are times you need to be firm but it should be the exception and you can still be compassionate and firm. 

Good luck!