Robocall Hardware modificarion

The FTC could make it illegal, with a proper punishment, for people who use RoboCall machines that do not have a mandated modification that sends a constant sound to inform the telephone provider (ATT, Verizon, etc.) so that they can block the call if the telephone subscriber wants Robo Calls blocked. The sound the RoboCall machine should send would be a constant 30K Cycles Per Second sound signal as long as the machine is turned on. Please note that the human ear is not able to hear sounds that are highter than 20K CPS so forcing RoboCalling machines to constantly send the sound would not interfere with the call information that is within the hearing range of the person being called.