Don't reformat your PC just yet. The "vMix D3D Startup Error" is a common issue, but it is almost always fixable. This article dives deep into what this error means, why it happens, and the exact step-by-step solutions to get you back online.
Search for and uninstall any instances of "Nahimic" or "A-Volute". Restart your computer. vMix Diagnostics vmix d3d startup error
Your GPU is waiting.