Swap the sockets were you have the tp links plugged into . This solved an issue with me before where the wired broadband dropped dramatically.
Tp links could be dodgy too . Unfortunately it’s a process of elimination here .
Also have you tried a speed test ? You need a certain minimum broadband to watch stuff like that , at least 10mg .
Reading that again would I be correct in thinking you have issues both with wireless & non wired ?