Wifi calling on iPhone with Deco X55 - Call drops and Poor voice quality moving around in network
Issue:
Where we stay the cellular signal is too weak to be able to make calls over 3G/4G. We have enabled WiFi calling on our iPhones (12 and 13) which allows calls to be routed through the WiFi IP connections. When moving around in the house, when the phone connection gets handed over from one mesh node to another, phone calls either drop or the voice quality reduces to point where the a conversation can't be had.
Configuration:
3 node X55 mesh network with 2 units on the 1st floor and 1 unit on the 2nd floor. Both satellite nodes are connected to the main node via CAT6E cable. There is a 150Gb fiber Internet connection on the back-end.
Have tried the following:
As per the support doc https://www.tp-link.com/latam/support/faq/1259/
1. Disabling and enabling SIP ALG
2. With and without enabling Port forwarding for UDP port 500 (IKE2) and port 4500 (IPsec Nat Traversal).
3. Reserved the IP address of the phone in DHCP
4. Also tried disabling and enabling Fast Roaming and Beamforming in the Deco app.
None of these measures improved the ability to have WiFi calls smoothly transition from one mesh node to another. The issue is perfectly repeatable every time.
By sitting in one place or staying within the vicinity of one node, the issue is minimized. This is obviously not practical.
TPLINK please advise as this issue has been going on for a long time and I am unable to resolve it.