Where does Edmund Burke explain aristocratic eccentricity as a reaction to the influx of non-titled country gentlemen?

Where does Edmund Burke explain aristocratic eccentricity as a reaction to the influx of non-titled country gentlemen?

I am looking for the source of a notion of Edmund Burke's that the English aristocracy turned to eccentric behavior in order to distinguish themselves from the “new men” who were acquiring estates in the country and aping the aristocrats' lifestyle and deportment. It struck me as a strikingly modern psychological-sociological observation, especially in the way that it teeters on the cusp between perceptive and outlandish. (I am quite sure the theory was Burke's, but not 100% sure - likely from the “Reflections” or from one of his speeches on Warren Hastings.)