New AirPods Max firmware update fixes battery drain issues when in Smart Case

Earlier this week, Apple released a new firmware version for AirPods Max. While Apple does not provide any sort of release notes for new AirPods firmware updates, it appears that this update resolves an issue that caused the over-ear headphones to lose battery life quickly when in the Smart Case.


The AirPods Max include a Smart Case that is designed to put them into a lower-mode to preserve battery life when not in use. The idea is that you put them into the Smart Case and they immediately enter a “low power mode,” then into an “ultra-low power mode” after 18 hours.

Since the AirPods Max headphones were released in December, however, many users have complained that the battery will drain from 100% to 1% or 0% overnight, even when left inside the Smart Case.

As we reported in January:

There are growing reports of an AirPods Max battery drain problem on the Apple Support Forums, Reddit, and elsewhere. Some owners are reporting that their headphone battery is draining from 100% to 1% or 0% overnight, even when left inside the official Apple case designed to drop them quickly into ultra-low power mode.

This issue appears to have been fixed with a firmware update for AirPods Max this week.

This week’s AirPods Max update

Testing done by 9to5Mac’s Gui Rambo shows a major difference in idle battery usage of AirPods Max when in the Smart Case after updating to firmware version 3C39. This is visualized in the two charts shown below, which show battery drain every 30 minutes for intervals of two hours.

As you can see, the AirPods Max lose very little battery when in the Smart Case with the new firmware. Battery loss was much more aggressive prior to this week’s firmware update.

AirPods Max battery drain prior to firmware 3C39 while AirPods Max are in the Smart Case

Battery drain with firmware version 3C39 while AirPods Max are in the Smart Case

Based on real-world testing and code findings, the update also appears to make a change to how long it takes AirPods Max to enter the “ultra-low power mode” when in the Smart Case. Previously, AirPods Max would enter this mode after 18 hours, but with firmware version 3C39, this appears to have been significantly shortened to around 30 minutes.

Finally, the update also improves compatibility with iOS 14.5 and resolves an issue where AirPods Max would crash shortly after being connected to a device running iOS 14.5.

How to update your AirPods Max

As we explained earlier this week, Apple does not make it possible to manually update your AirPods to new firmware releases. Instead, AirPods Max should update when they are connected to power and nearby your iPhone.

To check your AirPods firmware version:

  • Open the Settings app on your iPhone
  • Navigate to the “Bluetooth” menu
  • Find your AirPods Max in the list of devices
  • Tap the “i” next to them
  • Look at the “Firmware Version” number

The newest AirPods Max firmware version is 3C39. If this is what you see in the Settings app, then it means your AirPods Max are fully updated.

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Avatar for Chance Miller Chance Miller

Chance is an editor for the entire 9to5 network and covers the latest Apple news for 9to5Mac.

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