usb_audio: Enabling speaker causes Windows Pro 11 USB 2.0 Audio Driver to fail to start the device

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CircuitPython version and board name

Adafruit CircuitPython on Adafruit QT Py RP2040 - version 10.3.0-alpha.4

Code/REPL

# In boot.py
import usb_audio
usb_audio.enable(speaker=True)

# In code.py
import board
import neopixel

while True:
    status_led = neopixel.NeoPixel(board.NEOPIXEL, 1)
    status_led[0] = (255,255,255)
    status_led.write() # Just to indicate that the board has reached this point

Behavior

The code successfully passes from boot.py to code.py but Windows 11 Pro 25H2 using the Microsoft USB 2.0 Audio driver version 10.0.26100.9168 08-Aug-2026 has a driver error - This device cannot start. (Code 10)

This disables the PC audio speaker device and we can't get any audio to flow from the PC to the board.

Description

The board is using an Adafruit QT Py RP2040 connected to an Adafruit I2S Audio BFF connected to an 8 Ohm 3W speaker.

Additional information

Contacted #circuitpython-dev on Discord and connected with foamyguy#2825 and tannewt (he/him). They directed me here and pointed out the implementation code https://github.com/adafruit/circuitpython/blob/main/shared-module/usb_audio/USBSpeaker.c