Apart from the speaker’s voice, hearing aid amplifies environmental sounds as well. As the human brain needs some time to adapt to the amplified sounds, it is recommended that the hearing aid user get used to listening in typical quiet environment first before using the hearing aid in more challenging and adverse listening environments (e.g. in groups and/or in noise). Modern digital hearing aid technologies also facilitate listening in noisy environment through automatic noise reduction / cancellation features or let the hearing aid user switch to specific listening programmes in the hearing aid to enhance communication in such environment.