Is there is queue at the other end ?

Sometimes when we call the billing dept of the mobile service trying to lodge a complaint about inflated telephone bills or charged for sms not made there is generally a long hold at the other end. We are made to listen to music before we listen to a human voice at the other end. And then we are irate due to no fault of the agent. It is just the large call volume and not his fault. And also fill up a detractor (0-6) survey that affects his/her pms rating. Is that justified?