A hearing aid includes: a first module accommodating first circuitry; a second module accommodating second circuitry; and an interconnecting member configured for interconnecting the first circuitry with the second circuitry; wherein the second circuitry comprises a memory for storing data relating to a configuration of the second module including the second circuitry, and data communication circuitry configured for transmission of the data relating to the configuration from the memory to the first circuitry.