Hi Paul,
Thanks for reaching out to Microsoft Q&A. The asio.sys block typically happens when the driver is unsigned, incompatible, or blocked by Windows 11 security. In Addition, please try the following solutions first:
1, Check Memory Integrity (Core Isolation). Go to Settings > Privacy & Security > Windows Security > Device Security > Core Isolation > turn Memory Integrity Off, restart, and test the driver.
2, Reinstall ASIO driver (fresh version). Uninstall the current ASIO driver from Control Panel > Programs and Features, then download the latest Windows‑11‑compatible version directly from your audio interface manufacturer’s website, reinstall, and restart.
3, Use manufacturer‑specific ASIO instead of generic ASIO4ALL. Many devices work reliably only with the vendor’s official ASIO driver. Avoid ASIO4ALL unless the manufacturer does not provide its own version.
4, Check for Windows 11 Driver Signature blocks. Open Windows Security > App & Browser Control > Reputation-based Protection > temporarily turn off Check apps and files, install the driver, then turn it back on.
5, Update chipset and USB drivers. Install the latest motherboard chipset drivers and USB controller drivers from your hardware vendor. Outdated USB drivers often cause ASIO load failures.
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