General Motors LLC (GM) is recalling certain model year 2014-2015 Chevrolet Spark vehicles manufactured April 30, 2014, to May 20, 2015, and 2015 Chevrolet Sonic vehicles manufactured June 18, 2014, to June 10, 2015. In the affected vehicles, equipped with the base radio and OnStar, the radio may lock up due to a software issue, causing the display to go blank and all audio functions to cease. Because of this, there may be no warning chimes such as the reminder to buckle the seat belt and the key being left in ignition when the driver goes to exit the vehicle. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 208 “Occupant Crash Protection”, and 114 “Theft Protection.”