TM87V

Hi, wondering if anyone has experienced the dreaded Wastegate rattle? Mines started to do it (2009 135i) although it's only done 35,000miles. Have had it looked at by Birds BMW where I bought the car and have been told its normal, I find that a bit hard to believe on what was new a £40k car. Anyone know of any permanent, non bodge fixes? Any help much appreciated. Cheers