I'm about to smash my head against a brick wall if I can't figure this out soon.
A business I look after has just moved office picked up all the IT systems and installed in the new office, however, BT Cloud Voice phones will not connect. The only thing different is the ISP we have changed from BT FTTC to Virgin Media (27Mbps vs 500Mbps) no brainer, BT Cloud Voice will not connect. I am seriously thinking VM is blocking the traffic? Has anyone ever come across this before?