[Source] A sonic jammer was a tool used as a weapon by Quarg's father, a well-known pirate who was defeated by the Jedi Knights of the Galactic Republic. With a group of jammers spread throughout the Korteen asteroid belt, he wrecked passing ships and tore them apart for salvage. The Old Republic eventually ran him off, and he fled to Drexel. Once there, while using the jammer to draw starships to the surface so that the pirates could salvage their metals, he discovered that the devices affected the hearing of the Sea-dragons, and he tried to defeat the Dragon Lords by using the jammers on their mounts. Han Solo and Luke Skywalker destroyed the devices, allowing the dragons and Dragon Lords to defeat Quarg.