@Tomlink Hello Dear same issue i have found in my Apple TV 4K. I am open it and soldering cables and make USB cable. it's need ipsw file. Previously i have crashed my Apple TV 4K then i am doing same process and using checkra1n tool so my apple tv 4k is start again normally. But now my iOS version is 15.1.1 and unfortunately checkra1n not support this version.
mistrykm4u
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