A quick post to help anyone else, as I couldn’t find this info easily on the web. In the middle of the night, I was awoken by my Nexus 6 announcing an “Incoming call from unknown number”, despite the fact I had priority mode on and it shouldn’t have said anything.
In any case, this seems to fix it:
- Go to Settings, Accessibility, and click on “Talkback”, even if it says Talkback is “off”.
- Click on “Settings” under Talkback (at the top right)
- Disable “Speak caller ID”