NOTE: Found in the General Settings Menu and is only applicable to tablet installs. This feature does not affect installation on aftermarket Android head units
Tablet headphone jacks have built in little amplifiers. These are what drive the power to the headphones but in the case of Brainiac install the headphone jack is providing an audio output to the sound system of the vehicle.
These little amplifiers turn on/off in the tablet when it detects that it is going to play audio. When no audio is playing they turn themselves off to conserve power. However, when they turn off it can sometimes create noise across the sound system (hiss, buzz etc).
By turning on the Amplifier Keep Alive the software will keep the headphone jack amplifier powered even if no media is being played on the tablet to attempt to remove any extra noise on the audio channel. You can turn on/off this feature simply by tapping on the Amplifier Keep Alive option to toggle it to YES/NO.