The present subject matter relates to method and apparatus for processing sound by a hearing assistance device. In one example, the present subject matter is an apparatus for processing sound for a hearing assistance device, comprising: a microphone adapted for reception of the sound and to create a sound signal relating to the sound; a transducer that produces an output voltage related to motion; a signal processor, connected to the microphone and the transducer, the signal processor adapted to process the sound signal and the output voltage, the signal processor performing a vibration detection algorithm adapted to adjust hearing assistance device settings for a detected activity; and a housing adapted to house the signal processor.