@woozle I finally bought a double shielded USB3 extension cable and put the USB disk far away from the route and it works! 2.4 GHz network is not interrupted anymore.

The problem happens with any USB stick or an external USB disk. I'm thinking to return the device to the shop. Or is there a solution? I worry it's a hardware issue...

It seems that currently the VPN Server (especially WireGuard and OpenVPN) supports IPv4 only. As more and more Internet providers offer public IPv6 address only, it's important to be able to connect...

General DDNS for IPv6 is needed.

Any idea why even the port 22 doesn't work from outside for IPv6?

@Marvin_S Thanks for info, that's really sad as the VPN and IPv6 support was the main reasons to buy this router . But actually the IPv6 VPN connection works from the home network, so I guess there's...