Cannot Open Focusrite Usb Asio Error Code 0x54f

If both the Focusrite custom ASIO driver and Windows USB Audio class driver try to claim the device, you get 0x54f.

Fix – force exclusive mode via registry:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class4d36e96c-e325-11ce-bfc1-08002be10318<your-device-instance>]
"GlobalSettings"=dword:00000000
"ForceExclusiveMode"=dword:00000001
 cannot open focusrite usb asio error code 0x54f

Replace <your-device-instance> – find it via: If both the Focusrite custom ASIO driver and

reg query HKLM\SYSTEM\CurrentControlSet\Control\Class\4d36e96c-e325-11ce-bfc1-08002be10318 /s | findstr /i "focusrite"

Windows may cut power to the USB port to save energy, breaking the ASIO connection.

Fix:

Download USBlyzer (trial) or use Wireshark with USBPcap:

tshark -i \\.\USBPcap1 -Y "usb.transfer_type == 0x01 && usb.status == 0xc0000001"

0xc0000001 = STATUS_UNSUCCESSFUL – means USB host controller is resetting the device. Windows may cut power to the USB port

An outdated Focusrite firmware can cause unpredictable USB errors.