PS4 Audio issue

Just switched from PS3 to PS4. On first play I noticed the duty commencement sound plays through the speaker on the controller.
I play late at night at can't disturb others at home so turned down the volume of this on the PS4 options. However now, the audio for the duty commence does not play at all, it must solely play through the controller speaker.
I'd still like to be able to hear the audio alert, I often have my tablet fired up to check stuff while waiting for dutys and don't want to miss out due to not looking at the screen when it fires up.

Thats not a game related issue.......... Just turn off speaker settings on you controller.

You can use the headphone jack of your controller and then set the PS4 options (not ff options, but ps4 system options) to play all sound over the headphones.

you can turn it off in character setting.

ps4 system settings(not the game) allows you to disable the speaker on your controller and play all sounds over headphones, television, monitor, speakers etc.

There is a system configuration setting in game that will turn this off also. It's under the audio setting, reads something like "play notifications sounds through controller"