Weak Wireless Connection Crashes Entire Network

-When the wireless network goes down all wirelessly connected devices lose internet access and get disconnected from the network. Wired devices can still access the internet just fine though.

-After the wireless network goes down, scanning for available networks will reveal that our wireless network is still visible and at full strength but usually no one can connect to it. If someone does manage to connect to it though they will not have any access to the internet. For example, after the WiFi goes down and I somehow manage to reconnect my cell phone to the WiFi anyway, I will see the wireless symbol at the top of my cell phone screen and I will notice that only the upload arrow blinks, there will never be any downward arrow blinking which always let's me know my cell phone won't be able to access the internet. 

-Firmware version is V1.0.1.28. 

-My modem is Arris Surfboard model SB6183.

-No I have not tried doing a clean firmware install thank you for your suggestion.

Sometimes using the Windows 10 troubleshooting "Fix/repair my internet connection" corrects the issue and everyone can access the internet via WiFi again by reconnecting to our wireless network but that tool does not always work. All connected devices have unique IP and MAC addresses and obtain them dynamically from my ISP. I have already set the wireless channel to 6 in order to avoid interference, disabled UPnP, disabled guest network, & disabled dual band 5G so that the WiFi router only broadcasts at the 2.4 GHz frequency. I have not opened any ports in the port forwarding section. Indicated by the title of this tread I thought one pattern to this issue might be that a weak signal triggers the wireless network to crash, I still think there's something to that notion because the last crash I was spaced away a little out of my comfort zone, but now I'm really starting to think there may be more to this issue than just how distant one is from the router. I'm suspicious that my router may be going into a temporary lock-down state related to the PIN in the advanced router settings so I just disabled the PIN. I've taken good care of the router over the years, never overheated, never dropped etc. so I would be surprised if there's a hardware issue. This router works so well when it's not booting everyone off the WiFi lol. Any further assistance is much appreciated thank you.