Music is Mellow. But not when showing a house. Turn off the blaring radio or television. Let the salesperson and buyer talk, free of disturbances. Preferably out of the house.
Silence is golden.
Be courteous but don't force conversation with the potential buyer. He wants to inspect your house-not pay a social call. Be it ever so humble. Never apologize for the appearance of your house. After all, it has been lived in.