Bedbugs are becoming a common nuisance in many places. But cheap ultrasonic devices advertised as bedbug repellents don't work, scientists say. Carolyn Kaster/AP hide caption itoggle caption Carolyn Kaster/AP Shots - Health News Buzz Off: Bedbugs Unfazed By Ultrasonic Devices December 10, 2012 Once bedbugs settle in, the toll on your mental health and pocketbook can run high. So what about driving the bloodsucking insects off with high-pitched sounds? Scientists say gadgets that claim to do that are a waste of money.