Hear beeps 1 minute into the call, then lose call

[Frank86]

Using the latest version of 3CX on Windows Server 2016 with Flowroute.
Recently, we started having this problem where all calls start beeping (for one of the parties) one or two minutes into the call. The party hearing the beeps cannot hear the other party anymore and hangs up. However, he or she cannot call the other party because both parties still appear to be on the call.

Then, immediately after, I may place another call from my 3CX mobile app, and the call goes through, but I cannot hear anything and cannot hang up. When I tap on the hang-up icon in the 3CX mobile app, nothing happens. I have to hard-quit the app.

Is this a 3CX thing o a Flowroute thing? It seems to me something is seriously off. Is it just me?

 

[leejor]

What type of devices are you using...all 3CX Apps, or some other type of SIP phones as well? Does it happen on all? The beeping almost sounds like a call waiting thing, but not being able to hang up would appear to be something else.
Was anything changed, about the time this began happening?
Have you spoken to your provider, perhaps even having them on the line, when this happens?

 

[Frank86]

3CX mobile app (Android, iPhone)
Yealink T48 and T58 phones.
It happens on most calls.
The beeping is only heard on the mobile app (the app loses connection and tries to reconnect, and 3CX warns about that with the beeping), then the call is lost some time after.
Nothing was changed in 3CX or the network.
I have a ticket open with the provider as well.

 

[leejor]

It sounds like a network issue, affecting just the phones using the App. Does this happen on both Android and iPhones? Does this happen locally, on WiFi, when using 3/4G, or when using Wifi at a hotspot? How do you normally connect? Have you tried resticting the devices to one type of internet connection (Wifi) to see if there is a difference in behaviour?