The firmware tool does not always apply the PIN configuration

[Sacred-Shadow]

I’ve found the following issue in the DIY firmware tool:
Board: D1 Mini
IMU: ICM45686

The tracker is built exactly according to the default schematic - meaning only 3.3V / GND / SCL / SDA are connected.
Because the ICM45686 has no separate INT pins for the main tracker or the extension, the SlimeVR server always assumes that two trackers are connected.

Namely the main tracker and its extension.
Up to this point everything works.

However, since I didn’t build in an extension port, I only need the configuration with a single sensor.

So I deleted the 2nd sensor entry in the DIY firmware tool.
This leaves only one sensor with the following configuration:

After flashing, the server correctly shows only one tracker.
However, the tracker itself no longer detects the IMU.

According to the serial console, it now tries to access the IMU on D0/D1, even though the tool was configured to use D2/D1.

[INFO ] [SlimeVR] SlimeVR v0.7.1 starting up...
[INFO ] [SlimeVR] Vendor: Unknown, product: DIY SlimeVR Tracker
[INFO ] [Configuration] Found up-to-date configuration v1
[DEBUG] [Configuration] Found sensor calibration for SoftFusion (runtime calibration) at index 1
[DEBUG] [Configuration] Found sensor toggle state at index 1
[INFO ] [Configuration] Loaded configuration
[ERROR] [SensorManager] Can't find sensor type for sensor 0
[INFO ] [SensorManager] 0 sensor(s) configured
[ERROR] [SensorManager] Can't find I2C device on provided addresses, scanning for all I2C devices in the background
[INFO ] [WiFiHandler] Setting up WiFi
[INFO ] [WiFiHandler] Loaded credentials for SSID '#####' and pass length 17
[NOTICE] OTA updates allowed
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x01!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x02!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x03!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x04!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x05!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x06!
[ERROR] I2C: Too many transaction errors (6), please power off the tracker and check the IMU connections!
[WARN ] I2C (@ D0(16) : D1(5)): Unable to start transaction at address 0x07!
....