Don't you have such options in Advanced->System tools->System parameters (at the bottom) : These are a screenshots from the C2300 V2 emulator with FW v1.0.0: You can browse those by yourself: C2300...

Apart from this description in the website support section there's no way to see any further details regarding fixes/improvements, unless someone from TP-Link shares them. These are Tether compatible...

You should have an ADSL splitter. When the main line goes into the ADSL splitter it splits into 2 different lines (Internet and Phone). You should connect the Internet line to the VR400 DSL port, the...

It really depends on your usecase. Judging by the use of a range extender and a second router (in AP mode probably) I presume you need a better Wi-Fi coverage. If you decide to stay with the brand...

@Carlo.A You can watch this video as a guide to set up the router.

Go through the links I sent and see if that heps. If you still have that issue, try to scan again and see if the best channel for you has changed - you can change the channel according to the reslut....