6 sourced reports, with what to check before you buy. Each one links to the page it was reported on.
Costly or dangerous
Bluetooth stuck in pairing mode, cannot power off
Owner review on retailer (Thomann) page: after a few weeks the headphones got stuck in pairing mode and could not be powered off, rendering them useless. Another review on the same page reports 'Endless Bluetooth functionality problems.'
What to check. A Bluetooth fault can leave the unit stuck in pairing mode with no way to power off, effectively bricking it until a hard reset. This is a known, recurring failure mode, so buy from a seller with a generous return/warranty window.
Owner on a German Q&A service reports physical damage: the earcup suspension (Aufhängung) is broken on their Momentum 4.
What to check. A German owner reports the earcup hanger physically broken. This is a structural failure of the plastic suspension that requires a parts replacement and disassembly of the headband wiring to fix.
iFixit troubleshooting wiki lists battery failure as a cause of the headphones not charging or needing constant charging, with a battery-replacement guide.
What to check. If the unit will not power on or drains fast, the internal 700mAh battery may be failing. The battery is replaceable (OEM part AHB413645PCT) but the repair requires opening the left earcup, so it is not a user-serviceable quick fix.
Firmware 3.37.3 breaks multipoint Bluetooth pairing
Owner forum thread (ASR) with two independent owners reporting that firmware 3.37.3 broke two-device multipoint pairing; one could not reconnect to his laptop, another lost TV connection. One owner reports a hard reset fixed it, another says it did not.
What to check. Before buying, check which firmware a unit ships with; if it is 3.37.3, multipoint pairing may fail and a hard reset (hold power 20s) is the only workaround. This is a firmware fault, not a hardware defect, but it can make the headphones unusable with two devices.
Headband swivel joints and slider crack under torque
Independent repair guide site (LML Repair) describing the Momentum 4's plastic chassis and the swivel/slider joints as wear points that can crack under rotational torque.
What to check. The plastic swivel joints and headband sliders are the structural weak points; repeated folding into the case and daily adjustment stress them. If they crack, the earcup separates from the headband and repair is not trivial.
Left earcup crackles or cuts out (2025-26 reports)
Reviewer-consensus site aggregating owner reports of left earcups that crackle or cut out in 2025-26, plus creaking hinges at launch.
What to check. Recent owner reports describe the left earcup crackling or cutting out. If that happens, it is usually a broken internal cable or driver fault in the earcup, which requires opening the cup and re-soldering or replacing the cable.
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.
