A personal wearable monitor for monitoring a bio-electrical signal from a person. The monitor is adapted for detecting an upcoming seizure, and for providing an acoustical information signal. The monitor is provided with a first speaker (13) for providing the information signal, and a second speaker (14) is adapted for functioning as a microphone in testing if said first speaker is capable of providing a sound. The second speaker is also a back-up speaker. The monitor is adapted for providing a notification in the event that the second speaker (14) does not detect the generated sound from the first speaker (13).