# [Windows 11][Intel xHCI] bladeRF Micro A9 not working unless connected via USB hub

[Marshall710]

[Windows 11][Intel xHCI] bladeRF Micro A9 not working unless connected via USB hub

Environment

• Device: bladeRF Micro A9
• OS: Windows 11 Pro 23H2 (x64)
• PC: Lenovo ThinkCentre M90q Gen 6 (Type 13AD)
• USB Controller: Intel USB 3.2 Gen 2 xHCI
• bladeRF-cli version: latest (from official installer)
• Install path: C:\Program Files\bladeRF

bladeRF> i

Board: Nuand bladeRF 2.0 (bladerf2)
Serial #: 599e86f838ce4fb5b798cc26834b0b35
VCTCXO DAC calibration: 0x1d83
FPGA size: 301 KLE
FPGA loaded: yes
Flash size: 128 Mbit
USB bus: 1
USB address: 2
USB speed: SuperSpeed
Backend: libusb
Instance: 0

bladeRF> v

bladeRF-cli version: 1.9.0
libbladeRF version: 2.5.0

Firmware version: 2.4.0-git-a3d5c55f
FPGA version: 0.11.0 (configured from SPI flash)

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Problem

When I connect my bladeRF Micro A9 directly to the rear USB 3.2 ports,
the device appears correctly in Device Manager and bladeRF-cli -p shows it,
but any operation (including FPGA load or simple stream) fails with errors like:

Exception BladeRF Error: File or device I/O failure :: Retry 1/5
Exception BladeRF Error: No devices available :: Retry 2/5
Exception BladeRF Error: An unexpected error occurred :: Retry 4/5
Exception Division by zero :: Retry 5/5
Exception BladeRF Error: No devices available

However, when I connect the same board through a passive USB 2.0 hub (host-powered only),
everything works flawlessly — FPGA loads, streaming runs, and no disconnects occur.

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Additional Details

• The board is externally powered (I always power it before plugging into USB).

• Tested multiple USB 3.0 cables and ports — same behavior.

• Windows Device Manager shows:
  Vendor ID: 0x2CF0 (Nuand, LLC)
  Product ID: 0x5250
  Product String: "bladeRF 2.0"
  USB Version: 3.0 (5 Gbit/s)

• The bladeRF-cli tool detects the device as SuperSpeed (5 Gbit/s).

• The issue reproduces 100% on this Intel-based PC.

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What I Have Tried

• Reinstalled driver using Zadig (WinUSB latest).
• Reinstalled bladeRF software.
• • Disabled USB power saving in Windows Device Manager.
• Tested same board on another PC (AMD USB controller) — works perfectly.
• Tested on Linux — works fine directly, no hub required.

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Expected Behavior

The bladeRF Micro A9 should work directly on Intel USB 3.2 ports (xHCI) under Windows 11,
without requiring a USB 2.0 hub as an intermediary.

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Workaround

Connecting the board via a passive USB 2.0 hub makes everything work — even without external power for the hub.

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Question

Could this be a known Intel xHCI compatibility issue?
Is there a possible firmware or driver-side workaround for Windows hosts?

Thanks a lot for maintaining bladeRF — any help or advice would be appreciated!