4 sourced reports, with what to check before you buy. Each one links to the page it was reported on.
Costly or dangerous
Condensation build-up migrates into speaker holes and water-damages the drivers
Owners report humidity condensing inside the aluminum ear cups during normal wear, with droplets migrating into the speaker holes and damaging the drivers; a pinned subreddit post ties most hardware failures to condensation. Apple has not recognized it as a widespread defect and the headphones are not water-resistant.
What to check. Expect possible driver damage, random shutdowns, connection drops and audio loss after months of use, especially in warm/humid conditions. Repair is costly and Apple denies a design defect, so the buyer may face out-of-warranty replacement.
Three amber lights of death: unit becomes unusable and cannot be fixed by reset
Owners report a blinking-amber-LED defect that makes the headphones effectively unusable and that survives restart and factory reset; a Reddit user and CNET found a temporary freezer fix, suggesting microscopic cracks in internal wiring. Apple has not commented on the defect.
What to check. The unit can fail outright with no official remedy; the only reported 'fix' is temporary. This is a high-cost failure with no warranty path, so a buyer should weigh the risk of a dead unit after a few years.
Headband connector socket and plastic hinge in the earcup deform and break Bluetooth connection
An owner reports the plastic headband connector socket and hinge in the earcup deforming over time, causing connection symptoms that only a hard restart clears; they replaced it twice under AppleCare+ and again after warranty.
What to check. The earcup socket/hinge is a wear point that can cause connection failures and needs replacement; repeated failures can occur even under AppleCare+, and after warranty the owner pays out of pocket.
Headband mesh sags and dissolves, and the headband cannot be replaced
An owner reports the mesh canopy stretching, sagging and partially dissolving after a few years, with rubber fragments coming out of it, and says Apple does not replace the headband as goodwill. SoundGuys separately notes the headband is fixed in place with no official replacement part.
What to check. The mesh degrades over a couple of years and cannot be swapped officially; owners resort to DIY inserts or buy a new pair. A buyer should expect cosmetic/comfort degradation with no cheap repair path.
These reports come from the pages linked under each item: owner forums, repair guides and workshops. They are not a diagnosis of any one unit, and a careful check of the one you are buying still applies.
Text from the Kriko Over-ear noise-cancelling headphones catalog, version 0.1.1, under the CC-BY-SA-4.0 license.
