The CB radio in my wife's '01 GL1800 produces a loud, scratchy noise at slower speeds. It's dead clear at a stop, but when the bike is moving, she hears a static sound, like scratching whenever someone else transmits. Also, her transmissions produce the same noise to others. However, at higher highway speeds, her transmissions are clear, but she still hears the static. Any thoughts regarding this and how to remedy it? Thanks in advance.