InSound Medical has just released the Lyric hearing aid that can be worn 24 hours a day. It is meant to be inserted within millimeters of the ear drum and by virtue of its position and size, the internal battery doesn’t have to work too hard and can theoretically run for up to a month before a change is required. The Lyric is surrounded by a spongy material which enables moisture to escape, hence eliminating any infection risk. Doctors also claim that it is more efficient in its workings since sounds don’t need to be amplified too much. Should the Lyric’s battery die, the entire device will need to be replaced. An annual subscription fee of between $2,900 to $3,600 is required for both ears with unlimited replacements.