I have the following problem after recent upgrade of Android client to version 15.1.90 from 15.1.41. If you are on a GSM call and the 3CX client receives incoming call, the GSM call is blocked, neither put on hold, nor disconnected. You can't return to a GSM call, regardless whether you answered the 3CX call or not. The only option is to disconnect manually the GSM call and to redial it or wait other party for it. This was not happening with previous client 15.1.41. The phones affected are different brands like Samsung, Sony, different models, all updated to recent Android versions. What can be advised ? Can we downgrade to v.15.1.41 -- the 3CX client was automatically upgraded with automatic updates of applications on the phone. I have also customers complaining sharply to the issue and want to get rid out of 3CX client.