Use the physical volume knob or steering wheel volume buttons to move up/down. Use the to select.
Because these units are unbranded ("No-Name" Chinese head units), there is no central official website for downloads. Use these reputable community hubs to find your files:
Is your device currently ?
: Never use firmware meant for a different model; this can permanently "brick" (break) your device.
Adds newer Android security patches and improves Bluetooth, Wi-Fi, and GPS connectivity module performance.