Basic functions16Changing the volume Press to increase the volume. Press to decrease the volume.Key lock To activate the key lock function, press andfor 3 seconds.and shine for 2 seconds.All buttons except are locked.With activated key lock the on/off button flashesred if you press any of the locked buttons. To deactivate the key lock function, press andfor 3 seconds.and shine for 2 seconds. The key lockfunction is deactivated.Fade out ambient noises (mute) Press shortly to switch off the microphones ofyour hearing instruments. Press shortly to switch on again themicrophones of your hearing instruments.With this function you can fade out distracting noise fromenvironment (e.g. while watching TV).