Model : Archer C7

Hardware Version :

Firmware Version : 3.14.3 Build 150629 Rel.75798n

ISP :

Hi,

I have Archer C7 AC1750. I'm currently experiencing extremely poor signal quality. By posting this I'm seeking help in understanding the root cause of it.

In my setup, both 2.4Ghz and 5Ghz connections are on. They both work fine if I sit directly next to my the router. But I'm working from a room, less than 10 meters from the router.

Here's a video of the path from the router to my room – https://youtu.be/YucyiQeJEDU.

From my room, both 2.4Ghz and 5Ghz connections behave really poorly.

Here are the stats of my router:
Firmware version: 3.14.3 Build 150629 Rel.75798n
[*]Hardware revision: Archer C7 v2 00000000
Here's the the setup for both 2.4Ghz and 5Ghz connections:
2.4 Ghz

[*]Mode: 11bgn
[*]Channel: 11
[*]Width: 20Mhz

[*]5 Ghz
Mode: 11a/n/ac
[*]Channel: 149
[*]Width: auto

Here are the details stats for both connections gathered using WiFi Explorer 2.2 for macOS: wifiexplorer-2.2_20170113_110353.csv.

Being a programmer I'm interested not only in the fix, but also in understanding the root cause. I'm willing to dig a rabbit hole down to the linux-level router settings if it comes to that, but at the moment I have 0 ideas of what to look out for.

If my router's signal situation is totally normal (which, well, would be sad considering the router's price), I'm thinking of:
installing DD-WRT (the router will loose warranty; also, so no evidence that this will actually help in any way),
[*]buy range extender to improve signal's strength in my room. I'm already looking at these devices: http://www.tp-link.ua/ru/products/list-10.html; TP-Link RE210 AC750 looks promising; any other good extenders out there?
[*]buy a new router.