I am finding the Amazon Fire Stick on our television (downstairs) doesn't seem to like getting wifi through the TP-Link. In spite of it connecting, and showing a far stronger connection strength than the wifi direct from our router (upstairs), it often comes up with an error when trying to go to Amazon Prime, and then buffers every few seconds on live programmes (especially sports). 

If using the normal wifi from my router, on live broadcasts the picture quality dips at times, but at least there is rarely any pausing for buffering.

My wife loves watching the tennis, so I got the TP-Link to ensure she got the best picture quality possible, but using the TP-Link makes it impossible to watch matches when they keep pausing to download more of the broadcast.

Anyone got any ideas how to stop Amazon having to buffer when using the TP-Link?