I was seated in front of a woman like this on the Silver Star on New Years Day. She wouldn't stop yapping loudly on her cell phone and her kid was listening to his music loud enough to make the guy next to him deaf. After about 2.5 hours of this, I finally complained and the conductor said something to her. Maybe it's just because I live in a city with a "quiet car" on most (rush hour) trains - that I love to utilize - but I've never had problems with noise around me like I did on that trip.
Then again, that particular trip was a fiasco from the start as there was a guy in my car who was quite inebriated and grabbed both me and the woman behind me as we boarded in West Palm Beach. All the women in the car cheered when he was thrown off in Tampa. Apparently he had done it to all or most of us.