LED blinks every ~10s when brightness is set to off

[mitchross]

Describe the bug

With brightness cycled to off (short button press to the 0.0 level), the LEDs still blink faintly about every 10 seconds — noticeable in a dark room. When off, the light should stay completely dark.

Suspected cause (from reading the firmware)

The 10-second cadence exactly matches the Zigbee + BLE sensor push in main.c (zigbee_update_sensors() / ble_bthome_update() every 10 s).

led_task in led.c rewrites an identical frame to the WS2812-type pixels (IN-PI15) every 20 ms, so the data line is permanently active. When the radio TX burst coincides with one of those frames (current spike on the 3.3 V rail; DFS is also enabled via esp_pm_configure in main.c), the frame gets corrupted and the pixels briefly latch a random color before the next 20 ms refresh clears it — a visible blink even at intensity 0.

Possibly related: #54 (brightness appearing to change on its own could be the same corrupted-frame latching).

Hardware / firmware

• AirCube on USB power
• Firmware built from current master behavior (LED task logic unchanged since v1.5.x)

Proposed fix

Only write to the strip when the frame actually changes, keep a brief repeat window after changes so a corrupted transition write self-heals, refresh slowly (1 Hz) while lit as a safety net, and keep the data line fully idle once settled at off. PR incoming from my fork.

🤖 Generated with Claude Code

[mitchross]

Update: caught the actual root cause on the serial console. The device was in a reboot loop:

I (13633) zigbee: Waiting for coordinator (ESP_FAIL), attempt 4/5, retrying
E (16993) zigbee: Zigbee init failed 5 times – rebooting to reset radio
ESP-ROM:esp32h2-eco5-20240613
rst:0xc (SW_CPU),boot:0x1c (SPI_FAST_FLASH_BOOT)

A commissioned device whose coordinator is unreachable fails ESP_ZB_BDB_MODE_INITIALIZATION 5 times and then calls esp_restart() — which can't help if the coordinator is simply off/out of range, so it boot-loops every ~17 s forever. Each boot flashes the LED before button_init() loads the saved brightness from NVS, so a device with brightness set to off blinks all night.

Fix pushed to the PR: reboot at most once per power cycle (skip when the last reset was already ESP_RST_SW), then retry init with exponential backoff capped at 5 min; and start led_intensity at 0 so boots stay dark until the saved brightness loads.

🤖 Generated with Claude Code

[StuckAtPrototype]

thanks! I ll check it out