Model :

Hardware Version :

Firmware Version :

ISP :

TL-Wr841N
Firmware 3.16.9 Build 160419 Rel.48988n
Hardware WR841N v11 00000000
The router is connected to a cable modem and all the router settings are default except for clone IP and wifi security obviously.
PC is connected through a standard LAN cable. This is not a wifi issue.
What happens is, if I'm downloading a file larger than 200 or 300Mb the orange light comes on and the download fails after about one minute. I reset using the button and all returns to normal until I try to download again.
This has never happened with any other TP Link router and I've used half a dozen.
I'm positive this isn't an ISP issue because the cable modem doesn't drop the internet signal.
Any ideas?

Location is: Buenos Aires, Argentina
Service is cable 12mb/s