In the past, baby monitors only offered audio and there needed to be a cable connecting the sending unit, in the baby’s room, with the receiving unit. Now, however, there are a variety of wireless audio units, which allow parents to listen to their baby wherever they are in the house or even the garden. Audio units are worth considering if you need a unit which will work away from the mains for long periods. They will let certainly let you know if your baby is making any sounds, such as crying for attention and some models may allow you to talk to your baby to sooth them.