They replaced the sd card first, reader part, the usb cable, the whole radio unit, and finally they called GM and got a software patch that the dealership had to download it. It took them two day’s to get it to download to their computers. After the patch update it was fixed. It’s been okay every since. At first sometimes it would still pop up the error message but it would fix itself and work right then. Last week the only random thing was my backup camara had a blue screen on it. But it finally came back after it sat awhile and worked. Your best bet is to take it to a dealer and have them call GM and have them install the patch for the radio system.