You've spotted a very common native-speaker error. Many native speakers, even very well-educated ones, often slip in an extra 'would have' into the 'if' clause of third conditionals. Sometimes the 'have' is a 'v' sound, sometimes an unaccented syllable ( sounding like "If you'd uv done.." or "If you'd uh done..").
This is not standard grammar in the way that mixed conditionals are, and I would not recommend you copy it. But don't worry if you hear this. It's so common that we don't even notice it.