When you swallow, your eustachian tube opens and lets air into your middle ear from the back of your throat. Usually, this movement regulates the pressure in your ears and prevents infections. However, if it doesn't open and close as it should, or the passages become inflamed with allergies or a cold, you may hear crackling noises in your ears.

It's normal to hear popping and crackling sounds from your ears on occasion, but if this happens frequently or seems to be bothersome for you, it could be a sign of a serious issue. It is also common to have these sounds during changes in air pressure, such as when you're flying.

Ears are complex organs that work together with many small muscles, bones and nerves to translate soundwaves into something your brain can understand. The ear's outer ear brings soundwaves into the middle ear and sends them down to the inner ear where thousands of tiny nerve endings tell your brain what you're hearing.

Your ears are delicate and can be damaged by loud noises, exposure to environmental irritants, infections, and other health issues. These conditions can cause ear pain, ringing in the ears (tinnitus), dizziness or vertigo, and even hearing loss.

Crackling in your ear when swallowing is quite normal, and it is most often caused by the movement of the eustachian tube. This is a complex tube that opens and closes as you swallow to let air into the middle ear.