Originally Posted by clockwork.satan
Ok, so I completely taken my M8 back to scratch tonight and done a factory reset... And guess what? IT'S STILL DOING IT!
Surely there must be someone out there that's seen this before?
Sent from my HTC One_M8 using xda app-developers app
I'm in the same boat as you but with a different device (Sony Xperia Z Ultra GPE)
The speed is around 30Mbps on my desktop but only 3Mbps on my device.
The thing is, that this happens at home not on other routers I tried. So my conclusion is that it's something in the router.
You should try it too, test your connection on someone else's router to exclude the device from being the problem.