How do you know it only goes 3 quarters? When it finishes, it reboots and will always go back to upgrade firmware screen. This is normal. So you could select NO and see how it works. That screen will always appear until you delete the file from the SD card.Can someone please help me. I've got a sega megadive flashback 2018 and ice tried to upgrade to the custom firmware. Evertime I start the console up it asks if I want to upgrade I press left to upgrade but it only gets about 3 quarters then goes back to the menu asking if I want to upgrade. I've tried this several times and I can't get it to work. Can anyone help me with this.
I would guess the update worked. Try it out.
If not, try a different SD card.