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USB port on 4K Joey

I'm fairly certain it would work over ethernet, but wireless would be cooler. Looks like Dish didn't load the wifi adapter drivers on the 4K Joeys.

If anybody wants me to try it over ethernet I will.

I would assume that works on the 4K joey as it does on the other joeys. But as stated before you either need a gigabit network or directly connected to the Hopper. With Cat5e or better.
 
If anybody wants me to try it over ethernet I will.
That was one of the first things I did in the first week of getting my Joey 4K. You can't have both coax and Ethernet connected and since there was no advantage to sharing the traffic over my Gigabit Home LAN, I went back to the MOCA connection.