Apple TV by itself set Korean as language and I can't find a way out

When I powered up my brand new Apple TV 4 for the first time it spontaneously scrolled at lightning speed through the whole setup menu, each page visible for about a tenth of a second, while I watched in amazement. When it stopped the language was set as Korean. I think it's Korean. I could find no way to swap the language to English. Neither could the very nice Apple bloke who spent 45 minutes on the phone trying to sort out the problem. The best suggestion he could offer was for me to take the thing to an Apple store and have somebody reset it. Surely there's a way I could do it without having to undertake a train journey?