I think Bashdabish's advice was for Leon. Based on your speeds there has to be something more at play. Even at the standard 2.4GHz you vcan get way higher download speeds than what you posted.
Yours might not be a wireless problem at all. Do you get speeds any better when plugged in?
Ok, ran some tests (Ookla).
WIFI In conservatory (where I use it most of the time but furthest point from the router)
Download 8.83. Upload 4.93
WIFI Next to router
Download 55.36 Upload 27.58
Wired
Download 238.56 Upload 29.11
So clearly an issue with WIFI in conservatory. Is the wifi speed next to the router acceptable? Wired seems ok?
I did try an antiquated plug in adapter and there was an increase to Download 26.33 Upload 16.51, though it came with a whistling noise, but shows it would work!!
What is the best solution?

