Update: It is back!
The Problem with the Ghost or Phantom presence continues, and it might cause more and more problems! Spoiler alter: Microsoft is working on it.
The Voice capabilities for Microsoft Teams and Skype for Business Online keep getting better and better. Microsoft also launched the Call Analytics and the Microsoft Call Quality Dashboard as previews in Office 365. The last one is also known as CQD for a while. Both are great tools to Analyse Calls and drill down everything when someone reports an issue.
I migrated my user to cloud only a while ago. And I also use the Microsoft CloudPBX services for in- and outbound calls. I use both clients, Skype for Business and Microsoft Teams on my Mac, and the iPhone.
I also have a Polycom VVX 500 Desk-Phone that I use from time to time, but most of the time I use my iPhone with a Headset.
There is a lot that you can view and analyse. And it also helps you to decide things!
Here is something that I found very useful: My old network was fully managed and there is Quality of Services (QoS) configured. I moved to another location in January, where QoS isn’t configured yet. Even with a regular DSL connection (nothing else is available yet) the quality is mostly good! I had only a few echos, most of them on my iPhone while moving around, and i know that this is not the best idea.
Even when the Call Analytics shows that the call was poor, my experience was good. And I asked the other party while I was moving around in the office, and he told me that the quality was ok.