Why are people are holding placards ? What are they protesting against?

The car rolls up to a group of people carrying signs protesting the silence. They hold up signs welcoming Milo and friends and begin to write out what happened there. The King of Wisdom gave the Soundkeeper control of all the sounds and noises of the past and present. She ruled wisely and generously and kept all sounds for future reference. Over time, though, new people and their new sounds came and people began to not listen at all. When that happens, a sound vanishes, which made the Soundkeeper disconsolate. One day, Dr. Dischord arrived and cured everyone of their ails except for noises, so the Soundkeeper furiously banned all sound. It is a sad state and every day is harder and harder.