Hi everyone,
My mac mini wouldn't show any ringtone and pop up notification past a few weeks when it received calls in display sleep.
When the display is on, even screen saver on, it's worked.
However, once mac mini goes to display sleep (of course system keeps on), there is nothing, no waking the display up, no ringtone, no incoming message.
Only I could see a message "Missed FaceTime Audio call" on top right corner when I put manually the display on with mouse or keyboard.
Mac mini mid 2011 has been installed 10.11.3 and connected to Dell U2713H by mini display-port cable.
It's worked till around beginning February this year and it never happened before.
I tried disconnecting and reconnecting all plugs, SMC reset, PRAM reset, safe mode, memory check, creating new accounts, reinstalling system, installing clean Yosemite and El Capitan to external HDD etc. so far, but I couldn't fixed it at all.
Macbook with 10.11.3 connected to same Dell display by same cable works FaceTime perfectly even in display sleep.
I tried to call to myself from other device kept forcing display sleep using hot corner.
Also, there was nothing and "Missed FaceTime call" message on waking up display even kept sounding ringback tone from other device.
That means this mac mini might ignore any incoming call in display sleep.
There is no sound problem.
It keeps sounding music or time signals in display sleep.
I found similar post like my case.
Receive Facetime Call on Mac when screen off
I know one of the solutions is keeping display on, but I don't want it if possible.
I appreciate if someone helps me to fix it.
Regards
