Blue screen on startup

Hi, i bought an Ampown gd20 but when starts i only see a blue screen, i can hear a starting video but there is the blue screen, do you know how lo solve it or do a hard reset? Seems like my son move the screen resolution because the stick starts fine when i bought, so i want to factory reset the stick, or delete some configuration on the microsd. Thanks for help

This is not the forum for your device, we do not support those companies, please ask whoever sold you the device and post your concerns there.

Supported Devices · EmuELEC/EmuELEC Wiki (github.com)