I'm on the floor just listening to the sample calls.
<heavy breathing> "Can you tell more about how … uh, how account holder services can help me? And by the way, do you have any tips for growing tomatoes? I've been trying to grow them in my garden but the just won't COOPERATE."
I mean I already mute and mash till the line drops when they do come in, but they may not continue doing so at a low enough rate to keep that feasible, and boringly mechanical but necessary tasks are always prime candidates for automation in any case.
I don't have the time to set up Asterisk but this story inspired me to generate a collection of handy random DTMF tones that could semi-automate a mute and mash approach.