I posted the link to your video on the UrS forum of quattroworld. I thought it sounded like a playing card in bicycle spokes, i.e. something rotary hitting something. One UrS4 owner said: "Sounds external, fan clutch, PS pump, or a zip tie hitting the fan." Another made the excellent suggestion of temporarily disconnecting the serpentine accessory drive belt (take the tension out of the belt tensioner) to see if it something like the fan or power steering pump etc. (If it is them, the noise will go away with the serpentine belt not driving them)
Good luck.
Good luck.

the white
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