A wearable electronic device comprising: an electro-acoustic input transducer arranged to pick up an acoustic signal and convert the acoustic signal to a microphone signal (x); a loudspeaker; and a processor configured to: control the volume of a masking signal (m); and supply the masking signal (m) to the loudspeaker; CHARACTERIZED in that the processor is further configured to: based on processing at least the microphone signal (x), detect voice activity and generate a voice activity signal (y) which is, concurrently with the microphone signal, sequentially indicative of one or more of: voice activity and voice in-activity; and control the volume of the masking signal (m) in response to the voice activity signal (y) in accordance with supplying the masking signal (m) to the loudspeaker at a first volume at times when the voice activity signal (y) is indicative of voice activity and at a second volume at times when the voice activity signal (y) is indicate of voice in-activity, the first volume being larger than the second volume, wherein the masking signal serves the purpose of actively masking speech signals that may leak in to a wearer's ear despite of some passive dampening caused by the wearable device, wherein the processor is configured with one or both of: - an audio player to generate the masking signal by playing an audio track; and - an audio synthesizer to generate the masking signal using one or more signal generators. an electro-acoustic input transducer arranged to pick up an acoustic signal and convert the acoustic signal to a microphone signal (x); a loudspeaker; and a processor configured to: control the volume of a masking signal (m); and supply the masking signal (m) to the loudspeaker; control the volume of a masking signal (m); and supply the masking signal (m) to the loudspeaker; CHARACTERIZED in that the processor is further configured to: based on processing at least the microphone signal (x), detect voice activity and generate a voice activity signal (y) which is, concurrently with the microphone signal, sequentially indicative of one or more of: voice activity and voice in-activity; and control the volume of the masking signal (m) in response to the voice activity signal (y) in accordance with supplying the masking signal (m) to the loudspeaker at a first volume at times when the voice activity signal (y) is indicative of voice activity and at a second volume at times when the voice activity signal (y) is indicate of voice in-activity, the first volume being larger than the second volume, wherein the masking signal serves the purpose of actively masking speech signals that may leak in to a wearer's ear despite of some passive dampening caused by the wearable device, wherein the processor is configured with one or both of: - an audio player to generate the masking signal by playing an audio track; and - an audio synthesizer to generate the masking signal using one or more signal generators. based on processing at least the microphone signal (x), detect voice activity and generate a voice activity signal (y) which is, concurrently with the microphone signal, sequentially indicative of one or more of: voice activity and voice in-activity; and control the volume of the masking signal (m) in response to the voice activity signal (y) in accordance with supplying the masking signal (m) to the loudspeaker at a first volume at times when the voice activity signal (y) is indicative of voice activity and at a second volume at times when the voice activity signal (y) is indicate of voice in-activity, the first volume being larger than the second volume, wherein the masking signal serves the purpose of actively masking speech signals that may leak in to a wearer's ear despite of some passive dampening caused by the wearable device, wherein the processor is configured with one or both of: - an audio player to generate the masking signal by playing an audio track; and - an audio synthesizer to generate the masking signal using one or more signal generators. - an audio player to generate the masking signal by playing an audio track; and - an audio synthesizer to generate the masking signal using one or more signal generators.