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Android devices' signal amplification issue

Android devices' signal amplification issue

Owned by Petar Spaseski
Feb 26, 2025
2 min read

Some Android devices have users experiencing an amplification problem. This issue is specific to certain devices and is caused by the system's automatic gain control (AGC). The device recognises the sensor as a microphone, and the AGC is likely the culprit, even though the sensor is actually an accelerometer.

 

Here are some ways you can try to turn off or reduce automatic amplification on your device:

 

  1. Check "Disable USB Audio Routing" in Developer Options

Android devices often apply automatic gain control (AGC) differently based on audio settings. Try disabling USB audio routing:

  • Enable Developer Options:

    • Go to Settings → About Phone → Software Information

    • Tap Build Number 7 times until Developer Mode is enabled

  • Disable USB Audio Routing:

    • Go to Settings → Developer Options

    • Scroll down and find "Disable USB audio routing"

    • Turn it ON (this prevents Android from applying audio processing to external devices)

    • Restart the device and check the signal levels again.

 

  1. Check "Adapt Sound" and Sound Assistant Settings

Some devices have built-in sound enhancement features that may affect the USB microphone input.

  • Go to: Settings → Sounds and Vibration → Advanced Sound Settings → Adapt Sound

  • Try disabling any enhancements or set it to "Off" for external audio devices.

  • If you have Samsung’s Sound Assistant app installed, check for audio processing settings there.

 

  1. Use ADB to Disable AGC (Advanced Users)

If the settings above don’t work, you can try using ADB (Android Debug Bridge) to modify the audio settings:

  • Enable Developer Options (if not already enabled).

  • Enable USB Debugging:

    • Go to: Settings → Developer Options

    • Turn ON USB Debugging

  • Run ADB Commands (on a PC with ADB installed):

    • Connect the device via USB and run:

      • adb shell settings put global audio_offload_disabled 1

      • adb shell settings put global audio_policy_engine_enable 0

    • Restart the device and check the signal levels again.

 

  1. USB Settings

USB Configuration: When you connect the accelerometer, a notification might appear related to USB connection.  Check if you can change the USB configuration (e.g., from MTP to something else). This is a long shot, but sometimes changing the USB mode can affect how the device interprets the connected hardware.

 

  1. Hardware Considerations

If none of the software solutions work, consider:

  • Using a USB audio interface or an OTG adapter with gain control to bypass Android’s internal gain settings

  • USB Hub/Adapter: Try connecting the accelerometer through a powered USB hub.  This can sometimes help with devices that are finicky about USB power and might influence how the device sees the accelerometer.