STM32WB09 fails during Bluetooth connectivity

[mdk]

Describe the bug
It seems all common Bluetooth samples fail during Connect stage on a vanilla NUCLEO-WB09KE board — both in peripheral and central roles. Advertising itself works, scanning as well.

To Reproduce

1. Install zephyr-4.1 using the usual steps
2. west blobs fetch hal_stm32
3. Compile ie. peripheral_ht sample for board nucleo_wb09ke/stm32wb09 & flash
4. Use helper tool on iOS or Android or Mac (ie. LightBlue) to inspect BLE devices
5. Find the Nucleo board advertising itself as Zephyr Temperature Sensor
6. Click connect

Expected behavior
Board can be connected to and service/peripherals can be inspected.

Experienced behavior
Connection stalls on the helper app and never completes. Nucleo logs show "connected" and "disconnected" events shortly after.

Logs and console output

*** Booting Zephyr OS build v4.1.0 ***
[00:00:00.009,000] <inf> bt_hci_core: Identity: 02:80:E1:00:00:00 (public)
[00:00:00.009,000] <inf> bt_hci_core: HCI: version 5.4 (0x0d) revision 0x1064, manufacturer 0x0030
[00:00:00.009,000] <inf> bt_hci_core: LMP: version 5.4 (0x0d) subver 0x0000
Bluetooth initialized
no temperature device; using simulated data
Advertising successfully started
Connected
Disconnected, reason 0x08 

(logs with DBG below)

Environment:

• OS: MacOS
• Toolchain: Zephyr SDK
• Version: both 4.1 branch and recent (20Mar) 1dd9308e2f784aa07bdc3cc00387c0a0c8b58dbe
• Board: NUCLEO-WB09KE

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[mdk]

Full log with DBG enabled:

stm32wb09.txt

[mdk]

Noticed some differences after more testing:

On iOS/MacOS (NRFConnect app, LightBlue app) the connectivity never succeeds.
On Android (NRFConnect app on Pixel) it does ~75% of the times on first try but never does on secondary try (in examples that resume advertising ie. peripheral_hr).

[msmttchr]

Tested "*** Booting Zephyr OS build v4.1.0-1132-gc05cfbf15eeb ***":

• Android 12 (Samsung S10e) looks good.
• iOS 18.3.2 (iPhone 11) fails.
• iOS 18.3.2 (iPhone XR) looks good, it connects and reconnects without problems.
• Android 14 (Pixel 7a) looks good, also in reconnections
• iOS 15.3 (iPhone 8) looks good

@mdk, do you have sniffer log? Could you send also the exact iPhone and Pixel models?

[mdk]

I'll be able to send sniffer logs next week. For now the failing setups on my end:

• iOS 18.3.2 (iPhone 13) fails
• MacBook Pro 14" 2021 (MacOS 15.3.2) fails

On Android, what works initially (75% rate) but never after reconnect:

• Pixel 8a (Android 15) fails in reconnects