Thanks for the detailed response,
@Tell. You're right that the menu is accessed by holding down the bottom-right button on this unit.
I went through everything again and got 480T on the unit now. It might simply have been that I forgot to unplug my dashcam from the USB, but I went with a fresh download, slow reformat of the SD card, and extracted everything directly to the SD card rather than copying over from Windows - so a few variables in play and I can't say exactly what made the difference. Hopefully some of it will
help other people.
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