Check the speed from a port on the router compared with a port in your living room (on your powerline adaptors shiz). (Goto fast.com and see how big the number is) If there's a large difference then the problem is your connection in the house. If theres not a big difference the issue is your actual internet.
If its in your house im guessing by "bt plug things" you mean a pair of powerline adaptors one in the kitchen and one in the lounge? They're great when theyre great but when they not theyre pointless. Depends if they are transiting breakers, how your house is earthed, etc. Sometimes massive load on the same socket or spur can fuck em too. Try moving the living one to the kitchen on a different socket and seeing if its better or worse, and same thing with everything in the kitchen unplugged. If its better then either theres a shitty breaker or something worse between your living room and kitchen. If its not better then the plug adaptors either jsut suck balls or
dont play well with your house. (ForEG shitter adaptors generally work better in shitter houses because they dont use earth line)
If its your internet line theres stuff you can do but its wont help much other than buying better internet. If you're using ADSL you can shorten the distance from the modem to the master socket, remove any extensions and whatnot to phones and get a bellwire isolating filter for your modem but in general if youve bought or can only get shit internet you're gonna be stuck with shit internet. Sorry.
If its in your house im guessing by "bt plug things" you mean a pair of powerline adaptors one in the kitchen and one in the lounge? They're great when theyre great but when they not theyre pointless. Depends if they are transiting breakers, how your house is earthed, etc. Sometimes massive load on the same socket or spur can fuck em too. Try moving the living one to the kitchen on a different socket and seeing if its better or worse, and same thing with everything in the kitchen unplugged. If its better then either theres a shitty breaker or something worse between your living room and kitchen. If its not better then the plug adaptors either jsut suck balls or
dont play well with your house. (ForEG shitter adaptors generally work better in shitter houses because they dont use earth line)
If its your internet line theres stuff you can do but its wont help much other than buying better internet. If you're using ADSL you can shorten the distance from the modem to the master socket, remove any extensions and whatnot to phones and get a bellwire isolating filter for your modem but in general if youve bought or can only get shit internet you're gonna be stuck with shit internet. Sorry.