To ensure the system successfully registered the new software: Turn the unit if it hasn't turned off automatically. Unplug the USB flash drive from the front panel.
Plug the USB drive into the front panel port. The display will say “UNSUPPORT” —this is normal. Press and hold the button on the front panel. The display should change to “UPGRADE.” The process takes about 20 seconds. Yamaha Cd S303 Firmware Update