Crackling is usually the eustachian tube opening and closing against congestion or pressure.
The tube between your middle ear and throat equalizes pressure and drains fluid; when a cold or allergies gum it up, you hear pops and crackles and the ear can feel full or underwater. NHS guidance on eustachian tube dysfunction lists popping or crackling sounds as a common symptom and says the problem is often temporary, fading as the congestion clears. Earwax moving against the eardrum and jaw joint clicks are the other usual suspects. Pain, discharge, dizziness, one-sided hearing loss, or crackling that persists beyond a couple of weeks deserves a GP visit.
What to do
Common questions
Why do I hear crackling in my ear?
The most common cause is your eustachian tube misbehaving. That narrow tube runs from your middle ear to the back of your throat, equalizing pressure and draining fluid; when it gets sticky or blocked, usually after a cold, with allergies, or around flights, you hear crackling, popping, or clicking as it opens and closes, often with a full or underwater feeling and slightly muffled hearing. NHS guidance lists popping or crackling sounds among the common symptoms of eustachian tube dysfunction, and notes it is usually temporary. It typically fades as the cold or allergy settles. Helping it along: swallowing, yawning, chewing gum, and gentle pressure-equalizing maneuvers, plus treating the underlying congestion. Two other causes worth naming: earwax shifting against the eardrum can crackle, and jaw joint problems can click into the ear because the joint sits right next to the ear canal. See a GP if the crackling comes with pain, discharge, fever, dizziness, one-sided hearing loss, or lasts more than a couple of weeks, since those patterns point to ear infection, wax impaction, or something that needs a look inside.