US Patent 9232322 Hearing aid devices with reduced background and feedback noises

A personal sound processing apparatus has an earphone; a microphone; an electronic sound processor connected between an automatic gain controller (AGC) and a digital volume controller, an automated feedback tracker operatively connected to the microcontroller, and an audio signal amplifier to amplify audio signals which level is controlled by the digital volume controller. The microcontroller is configured to execute electronic instructions for recognizing at least one of a feedback noise condition and a background noise condition in the audio signals and to send a control signal to the digital volume controller to adjust volume level in response to presence of the at least one of the feedback noise condition and the background noise condition.