I have installed a new Vigor 2927ax at a client with pretty much standard config.

WAN2 has a pppoe connection.

All mobile devices connect to a Guest wifi network on LAN2.Wifi 2.4Ghz and 5Ghz all active with the same SSID and PW for Guest network

Routing document for ALL traffic on ALL Lans to go Via WAN2.

This is a very poor mobile reception area so they user Wifi Calling.With the previous TP-Link basic router they were all able to use Wifi calling. However now with the Vigor Android phones can use wifi calling but iphones cannot.I have tried all the usual steps on the iphones, (except the Big Hammer!).

With Airplane mode on the iphones say there is no Network Connection for Wifi Calling, but other apps such as WhatsApp work fine.

This is very similar to https://www.draytek.co.uk/forum/routers-and-firewalls/22929-wifi-calling-apple-disconnects

But there was no solution posted.

Has anyone else seen this with Vigor?

Cheers

For anyone who needs a solution:

Hardware Acceleration is on by default on the 2927ax.

Turning Hardware acceleration OFF appears to resolve the issue.