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Sony makes great audio gear ranging from home theater systems to personal audio wearables like headphones. Its flagship true-wireless earbuds from 2021, theWF-1000XM4, sound incredible while offering conveniences like best-in-class active noise cancelation, wireless charging, and excellent battery life. However, one XM4 user on Reddit had an alarming experience with their earbuds — the right one exploded inside the charging case without warning.
Based on a few picturesu/yangcong1982 shared, the explosion left the Sony WF-1000XM4 earbud in two halves, split along the adhesive-sealed seam. Obviously, the earbuds aren’t usable now, but there are no signs of combustion in the images shared after the fact. It doesn’t appear this accident hurt anybody.
Responding to questions on the Sony Headphones Subreddit, the unfortunate user clarified they placed the buds in their charging case and left them that way for two days prior to the explosion. This effectively rules out potential misuse as probable cause. The user said they charge the case using an Anker power bank, and the batteries were around 80% charged, ruling out damage due to overcharging and the use of an incorrect charger, even though most modern electronics have failsafe systems built in.
In the week leading up to the incident, the victim noted that the right earbud would discharge completely, even when the left one had 20 to 40% charge left. The gap eventually widened to a point where the right earbud died when the left one had 60% charge left. Interestingly, the user was running firmware version 1.4.2 on the earbuds — a buildinfamous for battery life issues. Other Redditors reported their earbuds running noticeably hotter on the same firmware, but one wouldn’t expect batteries on $280 wearables to go boom after just two years of use.
Thisisn’t the only caseof the buds exploding, and to Sony’s credit, the WF-1000XM4 has since received a firmware update (version 1.6.1 released in December 2022) specifically addressing the battery degradation issue. Sony has requested images of the damage, and is in touch with the Redditor to resolve the issue.
It’s just unfortunate this owner hadn’t updated the firmware. Should you still be running v1.4.2, we strongly suggest you update — if the new firmware is available in your region. From what we can tell, US users are still stuck with v1.4.2 even though v1.6.1 isrolling out in Asia. The brand cautions users the new firmware may result in shorter battery life overall, or uneven discharge in your buds, but has adedicated support documentfor people facing the issue. If you must use v1.4.2, at the very least, watch out for uneven battery depletion and hot earbuds, as they could be signs of an impending disaster. If your buds are damaged, Sony USA mighthonor replacement claims outside standard warranty periodbecause of the issue.
UPDATE: 2025-06-01 11:46 EST BY CHANDRAVEER MATHUR
Update: Firmware version 1.6.1 availability
The article has been updated to reflect the region-specific availability of firmware version 1.6.1 for the Sony WF1000-XM4, brought to our attention by@WriterAMichaelson Twitter. The firmware update contains a fix for the battery degradation caused by version 1.4.2.
