@Dreammaster007
I would assume that you're connecting wirelessly to each device.
if that's the case then this is probably due to a wireless interference between your devices, with neithbours wireless devices or your home appliances.
If your Telenet modem/router is located close to Archer A7 then disable its wireless radio and leave A7 to be the main wireless device, then test if that helps.
If they are not so close to each other then you can play with their wireless channels to minimize the wireless interference.
Follow this article:
https://www.metageek.com/training/resources/why-channels-1-6-11.html
to see how to scan wireless channels around you and select the least congested for your devices.
That's valid for both 2.4GHz and 5GHz bands except the non-overlaping channels which are considerably more for 5GHz.
Check this article to see how to design your dual band wireless network for capacity and coverage.
https://www.metageek.com/training/resources/design-dual-band-wifi.html