Yes a numbers of times when on the phone , I will ask the person to talk slower and they start yelling at me ! This happened so many times I now just hang if I am having a hard time and wait for daughter to help made the call ,if I can't wait I call back and hope I get someone I can hear. I will tell the person I said " slower " so why are you yelling at me ?" and they yell some more. I think some hearing people will never get it !Have you tried telling them what they can do when you say that you're hoh.
I imagine them slowing down their talking speed would help and taking in the call in a less noisy room? If possible of course