lost incoming call on pc - mobile rainbow no voice - strange behavior rainbow app

Since latest version we have more support tickets about people claiming that when they answer an external customer call on the computer that their mobile (rainbow app) starts ringing like another incoming call.

You can't answer the customer on the mobile or on the computer, looks like the line is lost. Both empty...

In call logs on the PBX nothing to see

It's not always, difficult to simulate but very annoying.