Digital Lifestyle Outfitters (DLO) have filed a lawsuit against Griffin and Belkin for patent infringement, reports the iPodObserver. The suit alleges that the companies are violating a DLO patent that covers a type of FM radio transmitter and charger that allows users to play an MP3 player’s music through a car stereo. “DLO feels that Belkin’s TuneBase FM and Griffin’s RoadTrip directly violate its patent,” notes the story. “Both products are iPod accessories that compete directly with DLO’s TransPod. Both suits were filed in the United States District Court for the Middle District of North Carolina.” DLO is seeking “injunctive relief, monetary damages, and enhanced damages for willfulness, claiming that both companies willfully violated the patent.”