1. A system for processing detected audio waveforms in a first mode and a second mode, comprising: a microphone configured for detecting one or more audio waveforms; a gesture detection sensor configured to detect one or more touchless gestures corresponding to different processing modes; a system clock configured to provide time stamps for the one or more audio waveforms detected by the microphone and time stamps for the one or more touchless gestures detected by the gesture detection sensor, the time stamps for the one or more touchless gestures indicating a starting time and an ending time of each detected touchless gesture; a buffer configured to store the one or more audio waveforms and information regarding the one or more touchless gestures; and one or more processors configured to enter the second mode and selectively process a detected audio waveform stored in the buffer in the second mode when a time stamp of the detected audio waveform is between a first time stamp of a first touchless gesture corresponding to the second mode detected by the gesture detection sensor and a second time stamp associated with one of the one or more touchless gestures.