Look for the "Unknown Device" with a yellow triangle (likely under Other devices ). Check IDs: Right-click it > Properties > Details tab.
By following this guide, you can turn that yellow exclamation mark into a smoothly running system where every Fn key press does exactly what you expect. acpi fnbt0000 0 driver windows 10
After a fresh install of Windows 10, many OEM-specific ACPI drivers are missing. Windows Update may not automatically fetch these niche drivers. Look for the "Unknown Device" with a yellow