Allow scanner to have new alert notification and more options

[sam686]

This have happened once to me, with a wrong subtitle bug. Voice sounds cleaner and in stereo, depending on the location of camera and Scanner, which is very nice. video: https://www.twitch.tv/videos/382561580

Later... being sad that it is just random and not all the time, with mono, random distortion of voice. https://www.twitch.tv/videos/382565659

When scanner is on, I would sure like to hear new alert voices come from the scanner, in stereo. When scanner is off, just keep it silent. The scanner itself probably need more options on which voice it should tune to, with players able to change volume of scanner's voice.