Firmware updates can cause glitches if old settings clash with new software.
: Never use firmware meant for a different model (e.g., YT9213 or YT9218) unless you are certain of compatibility, as screen sizes and button configurations vary.
) or forums like XDA-Developers host these "XY AUTO" update packages. The USB Method Format a USB drive to Unzip the firmware files into the of the drive (no folders). Plug it into the head unit's USB port. Settings > System > System Update