I installed MR 4.6.6 yesterday on two Android phones. (My center is in the test/build phase of deploying MR to our customers.) First of all I had to uninstall 4.6.1 before 4.6.6 would install, otherwise the installer would just say "App failed to install". However, it's working largely okay, except that every 2-5 minutes, the app is generating the notification sound without any notifications showing up (other than the "Collecting Location Data/Doing tracking task" banner that persists in the system tray when the app is in the background). This keeps on happening whether Track Me is on or off. I've confirmed there are no waiting CAD messages or events dispatched to me. It also does it if the app is in the foreground too.

CAD version is 9.2 MR5 (MR server 9.2 MR6)

Phones are Samsung Galaxy S7 Edge running Android OS 6.0.1 and Samsung Galaxy S4 running Android OS 5.0.1

Neither device exhibited this under MR 4.6.1.

I also have an iPhone 6 with 4.6.1 installed (iOS 9.x) and it is not making notification sounds except when it should (when receiving messages, status updates, dispatched to events, etc) - both Android phones do get these notifications properly as well.