Let's assume for a second that this is an issue with your hub as newapollo has suggested. Take one of the working ports that is currently used by another device, and try the V6 in that. I suspect that if other devices are working, that eliminates an activation issue - but swapping ports & cables would prove that either way.
Based on your explanation, I'd be beginning to suspect a V6 issue. Given that the boxes are physically close, does swapping between 2.4 & 5Ghz WiFi bands make any difference? I'd still suggest Ethernet given the choice, but all the same.
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