Electronics in a receiver-in-canal module

A hearing aid assembly comprising a first part being a behind-the-ear part and a second part being an In-the-Ear part, the first part comprising a DSP, the second part comprising an electronic-auxiliary-function-unit and a receiver, wherein the electronic-auxiliary-function-unit includes a microcontroller and is arranged for storing an identification string representing the receiver, and wherein the DSP is configured to request the identification string from the microcontroller and adapt audio processing for the receiver based on the received identification string.