Ooen your web browser and go to kabel.box , and login to the router's control page.
default username: admin
default password: password
Once logged in, click on the "WiFi" tab at the top. It will show you the basic info for your wireless network.
If you are using 2.4ghz, try changing the following settings:
For Channel, change "auto" to either 1, 6 or 11.
If using 5ghz change:
Channel- from "auto" to 100 or 120
Bandwidth- to 80
Transmission mode- to 802.11n/ac mixed
If using both:
Use the same settings as above, except change the 2 4ghz bandwidth to 20.
Apply changes, and wait for your router to restart. You should have a more steady signal, but if you find that it's still too weak around the house, you can either buy a wifi range extender on Amazon, or you try changing the 5ghz bandwidth to 40mhz, and reset again.
Hope this helps.