Another challenge with doing live sound for individuals who are speaking at a conference is that, in comparison with professional singers, individuals who are invited to speak at a forum may not be familiar with how microphones work. Some individuals may accidentally point the microphone towards a speaker or monitor speaker, which may cause audio feedback "howls". In some cases, when an individual who is speaking does not speak enough directly into the microphone, the audio engineer may ask the individual to wear a lavaliere microphone, which can be clipped onto a lapel.