Have a look at your wall socket, and in some cases there is a length of cable from it to a plug (which must be kept powered). If you had described your problems without referring to the TV box I would have suspected that you'd switched off the power supply and thus cut signals to the hub and so bringing down both your broadband and landline. However if you are just unplugging your TV box I cannot see how it affects your hub and you need a tech to attend.
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Hub 3.0, TP-Link Archer C8, TP-Link TL-SG108S 8-port gigabit switch, V6