Act before the spill dries
Disconnect any cable, remove the case and blot the exterior with a soft, lint-free cloth. Keep the top receiver opening downward so gravity moves liquid away from the slot. Do not press the cloth into the mesh or repeatedly raise the phone to your ear.
Note whether the spill was plain milk, flavored milk, formula or a sweetened drink. Added sugar increases the likelihood of sticky residue.
Separate free liquid from residue
Fresh milk can temporarily muffle the receiver like water, but it leaves protein, fat and sometimes sugar when it dries. A tone may move part of the free liquid; it cannot make those dissolved solids disappear. This is why sound can improve briefly and then become muffled again.
Do not assume louder playback will clean the mesh. Excessive volume adds stress without removing material attached to it.
Dry without forcing material inward
Place the iPhone in a dry area with airflow. Avoid heat, compressed air, rice, pins and cotton swabs. Apple’s liquid-detection guidance warns against heat, pressure, objects and particles around wet openings.
Do not pour water, alcohol or household cleaner into the receiver. Follow Apple’s current exterior-cleaning instructions for the model and keep openings from becoming saturated.
Test the receiver, not only the bottom speaker
After initial draining, disconnect Bluetooth and make a brief call in a quiet room. Compare audio at the ear with speakerphone. Clear speakerphone audio and a muffled call isolate the top receiver more effectively than music alone.
If the receiver still produces sound, use an earpiece-targeted Water Eject sequence with the top edge downward. Run it once, wipe away any expelled liquid and return the phone to airflow.
Reinspect only when dry
Once dry, remove any case or screen protector overlapping the slot and inspect under bright light. Do not scrape visible film. A small, clean, dry soft-bristled brush is appropriate only for loose surface debris under Apple’s speaker-cleaning guidance, not sticky residue behind the mesh.
Use the same short call test at moderate volume to judge whether the change is stable.
Escalate persistent or returning symptoms
Seek service when call audio remains muffled, crackling returns after apparent improvement, the receiver becomes silent or residue is visibly trapped. Also escalate for charging, heat, display, power or camera symptoms.
Tell the technician that the liquid was milk. That detail is more useful than describing the problem only as “water in the speaker,” because the residue changes what sound and home cleaning can accomplish.
Questions about milk in an iPhone earpiece
Is milk worse than plain water for the earpiece?+
Milk can leave fatty, protein and sugar residue, so persistent blockage or distortion is more likely after the liquid dries.
Should I rinse the receiver with water?+
Do not add liquid based on generic advice. Follow Apple’s cleaning guidance or obtain professional help for the specific model.
Can I use a cotton swab?+
No. A swab can shed fibers and push residue through the narrow receiver mesh.
When should the receiver be serviced?+
Seek service if calls remain muffled, crackling returns, no sound is produced or residue is visibly trapped after safe drying.