If I take any tablet and watch a video on DSL, it will soak the line. Not only that but if you used VPN that added even more overhead.
I see nothing wrong here.
I can't tell what's loaded beyond stock on the tablet. There's so much ADWARE on the apps that all you would have to do is install ONE BAD APP. Fix? Factory reset the tablet. Do not install apps.
Third and last problem: the phone seems to use almost all of the available bandwidth on my home ADSL connection.
As soon as the phone connects to my wifi, there seems to be almost no bandwidth available to my computer. The problem disappears when I switch off the phone's wifi.
Symptoms include the spinning pinwheel of doom on my Mac when my browser (Firefox) is loading ordinary web pages, interruption of audio streams, and extremely slow download speeds.
Normally, my download speeds over the ADSL connection are around 4 Mb/sec, sometimes as high as 5.6 Mb/sec.
Hardware & other details:
1. Galaxy Note 4 model SM-N910F
2. Android version 5.0.1.
3. Security software version MDF v1.1 Release 5; VPN v1.4 Release 4.
4. Running Freedome version 126.96.36.1992 (though problems seem to occur whether Freedome is on or off)
5. ADSL connection through Zen Internet
6. On Networks N300 router. I think this is similar to the Netgear router of the same model number.