Research Challenge: Medical TV volume

Today’s Research Challenge: Investigator JCM writes:

I went to my new doctor’s office and was horrified to see, in the waiting room, a large TV (and loud) on a stand with a handwritten sign attached which said, “DO NOT ADJUST VOLUME.  IT HAS TO BE AT THIS LEVEL.”

I loath TVs in waiting rooms, airline terminals, and almost anywhere I do not have the power to turn them off. I was very disappointed in my new physician’s practice’s decision.

The challenge is: What is the medical reason for keeping the sound at a fixed intensity?
For extra credit: Supply citations for any academic studies directly pertaining to this medical non-adjustment practice.

Improbable Research