External calls cutting out

[chrisjako]

In a school and we are suffering at the moment with really bad phone lines and calls cutting out mid conversation. This is only on external calls.

Our SIP trunk provider cannot see any issues with the trunks and from Wireshark traces I have sent over they seem to think that the issues are coming before it hits them. I have the 3CX server hosted on an high spec server running Debian and all phones on their own VLAN.

I have QOS on our internal HP switching for this VLAN and have also give VOIP Traffic priority and a guaranteed 40mpbs on our Smoothwall firewall

We are on a virgin media 1gbps leased line in the UK

the issue seems to be worse at times of high traffic within our school for example lesson change over and login

Does anyone have any pointers on this at all?

Any help now is greatly appreciated!

 

[JohnS_3CX]

Hi Chris,

Perhaps the QoS needs to be done on the WAN level, if VoIP has to compete with PCs for internet access.

But just to get the provider out of the way, you can call some internal extensions using your mobile app on LTE during times when external calls suffer. If it is indeed the internet access, then this call will also be degraded since it will also pass via internet.

Meanwhile if you have a backup link that is not in daily use, you can try moving the machine's access via this link and see if it improves since it will not be competing with anyone else.