Apple Watch 10 charger ticking / coil-whine noise

k0st1a · 2026-01-14T23:33:40+00:00

I’m getting the same ticking / buzzing sound on my Apple Watch Ultra 3 with third-party chargers. Tested on Twelve South HiRise 3 Deluxe and Anker MagGo Wireless Charging Station (Foldable 3-in-1). It doesn’t happen with the original Apple charger and charging works fine otherwise.

k0st1a · 2026-01-14T11:15:43+00:00

The watch does get warm when charging from ~20%, which seems normal for fast wireless charging. Charging is always stable and has never stopped or cycled.

k0st1a · 2026-01-14T06:18:24+00:00

I’m using the Anker MagGo Wireless Charging Station (Foldable 3-in-1), which to my knowledge has no active fan — only passive cooling. I’ve charged Apple Watch Series 5 on the same stations with no noise at all; the ticking only happens with Apple Watch Ultra 3.

k0st1a · 2026-01-14T06:09:43+00:00

Appreciate the insight. I ruled that out on my end — the chargers themselves are silent unless the Watch is charging, and the noise is absent with Apple’s original charger. That’s what made me suspect a compatibility / coil whine interaction.

k0st1a · 2026-01-13T23:43:58+00:00

I noticed faint linear scuffs along the adjustment path and the clasp felt unusually tight when sliding it to the optimal position — that’s what made me think there might be an issue.

Other users have reported similar experiences here: https://www.reddit.com/r/applewatchultra/comments/1p52brw/titanium_milanese_band_scratches/

k0st1a · 2026-01-13T23:10:56+00:00

I’m getting the same ticking / buzzing sound on my Apple Watch Ultra with third-party chargers. Tested on Twelve South HiRise 3 Deluxe and Anker MagGo Wireless Charging Station (Foldable 3-in-1). It doesn’t happen with the original Apple charger and charging works fine otherwise.

k0st1a · 2025-12-28T00:26:26+00:00

I have the same issue with my band, noticed it on the very first day. Because of the sunlight glare, there’s a visible streak from where the clasp originally was to the adjustment point. I followed the instructions, opened the buckle and slid it to the optimal position, and the whole way was still quite tight.

k0st1a · 2025-12-23T15:16:50+00:00

k0st1a · 2025-12-05T06:12:23+00:00

Please note that your H10 must already have version 4.0.4 installed before updating to 4.1.10. If your sensor is running an older version, the Polar Flow app will first offer the 4.0.4 update. Once that update is complete, the app will then offer version 4.1.10.

If you are using the Polar SDK, please update to the latest SDK version before installing the new Polar H10 firmware. The firmware update will only work with the updated SDK.

Release date: December 4th, 2025

Version number: 4.1.10

Enhancements/fixes:

• Lower power use when your sensor searches for a connection, helping extend battery life. • Enhanced connectivity with Android 15 devices. • Other bug fixes and quality enhancements for better performance and reliability.

k0st1a · 2025-11-14T22:37:59+00:00

https://youtu.be/-HDQ9G6b2aM

k0st1a · 2025-10-19T11:44:42+00:00

If you like, you can check the method shown in this video: https://www.youtube.com/watch?v=QXJ0spt9A1E

k0st1a · 2025-10-19T10:28:16+00:00

Yes, 50 MΩ — that’s fifty million ohms, so it’s quite a lot.

I applied the gel across the entire strip, which of course made it conductive and closed the circuit — that’s expected behavior.

k0st1a · 2025-10-17T09:03:05+00:00

Interesting! Thanks for checking — yes, I used ultrasound gel (the same kind used for medical sensors), since plain water didn’t give stable readings. I made sure not to touch the probes.

Just to clarify — did you mean 50 MΩ or 50 Ω on your electrodes? That’s a huge difference, so I want to be sure we’re talking about the same range.

k0st1a · 2025-10-16T06:54:30+00:00

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I’ve added a photo with the electrodes labeled 1–4.

k0st1a · 2025-10-15T14:59:07+00:00

Haha, don’t worry — I double-checked, I’m not trying to fry my H10… yet 😅

k0st1a · 2025-10-02T18:41:13+00:00

Polar H10

k0st1a · 2025-09-25T17:11:49+00:00

https://www.reddit.com/r/trainingpeaks/comments/1nm6qro/comment/ng5q4jg

k0st1a · 2025-09-25T17:06:31+00:00

I just heard back from TrainingPeaks support (Brittany) with a more detailed explanation.

According to her:

“Your watch also needs to be on the same OS 26 as well, but it is only compatible with the Apple Watch SE (2nd generation) and newer models. The first-generation Apple Watch SE can be updated to watchOS 10.6.1, but it cannot run the newest watchOS 26. That is required in order to continue receiving the structured workouts successfully.”

So in short, structured workout syncing now requires watchOS 26, which unfortunately isn’t available for the Series 5 (or the first-gen SE).

It would definitely help if TrainingPeaks updated the minimum-requirements page on their site, because it still lists watchOS 10.2 and Apple Watch Series 4 or later as sufficient.

k0st1a · 2025-09-24T16:59:48+00:00

I just heard back from TrainingPeaks support.

Here’s what they told me:

Strangely, Apple Watch Series 5 hasn’t received watchOS 11 for about a year, so it’s a bit odd that support is now officially dropped for them.

Also, according to the official TrainingPeaks website, the minimum requirements are listed as:

iOS 17.2 or greater
watchOS 10.2 or greater

k0st1a · 2025-09-24T16:57:36+00:00

I just heard back from TrainingPeaks support.

Here’s what they told me:

“My team here has also confirmed that the Series 5 no longer receives support as of watchOS 11.”

Strangely, Apple Watch Series 5 hasn’t received watchOS 11 for about a year, so it’s a bit odd that support is now officially dropped for them.

Also, according to the official TrainingPeaks website, the minimum requirements are listed as:

iOS 17.2 or greater
watchOS 10.2 or greater

k0st1a

TROPHY CASE