What's App/Hub on modem only - UDP? "unable to initiate call"

[jemski4]

I have just put my super hub 3 on modem only and connected a TPLink deco M5 system as the wifi just keeps on dropping out.  The jury is still out on that but 3 days in and all seems ok.

However, before I did this and now, my wife's work phone (she is a psychotherapist and does 50% of her work via whats app) intermittently says "unable to initiate call".  This can be at very bad times for her clients.

I am not a technical whizz and I read on What's App website that it might be something to do with UDP??

If I have put the hub on modem only, is this still a thing?  Please excuse my ignorance, I have no idea at which point in the network the UDP is a thing.

Does anyone know if I can do anything about this?  This is quite serious for my wife.

Many thanks in advance.

[Roger_Gooner]

The phone is using the Deco's WiFi to make WhatsApp calls. Maybe the WiFi is weak or some app is causing the problem.

[jemski4]

Thanks Roger.  The speed test says 170mbps so that is all good.

this is what What's App say

Check your network

Ensure your device is connected to the internet and you have a strong connection.

Try connecting to a different network on Wi-Fi or mobile data. Your current network might not be configured for User Datagram Protocol (UDP), which might stop WhatsApp calling from working properly.

That's what made me ask about this UDP thing

[Roger_Gooner]

Try mobile data in order to rule out a WiFi problem.

[Tudor]

"

this is what What's App say

Check your network

Ensure your device is connected to the internet and you have a strong connection.

Try connecting to a different network on Wi-Fi or mobile data. Your current network might not be configured for User Datagram Protocol (UDP), which might stop WhatsApp calling from working properly."

They are talking utter rubbish. You cannot disable or get rid of UDP, your network would not work at all without it.

[Client62]

Using the VM DNS with "Child Safe" enabled is known to block calls via WhatApp & FB Messenger and the like.

A fix would be to set your 3rd party router to use a public DNS e.g.Google DNS or OpenDNS.