I’ll start by saying I am technical, having been in IT support for over 30 years. That said this particular issues baffles me. TP link router Archer MR600, great signal as I’ve got a line of sight to the mast. Generally get 60 plus meg. All of the network is very stable apart from the TV. The TV works absolutely fine on the WiFi with an EE sim installed. As soon as the Smarty sim goes in, we get about 10 minutes of TV before it reboots and it does this very frequently. Remove the sim and all works well. I can use Amazon services on the TV without any crashes but terrestrial and catch up, bbc etc, I get regular crashes. I’ve reset everything and tried a new Wi-Fi profile. Reset the TV to factory default. The issue is only present she the smarty sim is n the router. I’ve not yet tried a full router reset, mainly because of all the smart tech in the house. I can’t understand why a sim in a router would have an effect on the TV that doesn’t have direct access to it. I have 2x MR600’s one slightly newer in design but they both have the same firmware. I’ll make up a cat 5/6 cable this week and see if a wired connection has the same effect. As I’ve been writing the TV has crashed 3 times, so I’m going offline to finish watching the film.