If you dump metered (by the Air Mass Meter) air to atmosphere you will cause more problems as the ECU will make the mixture too rich as there will be less air in the system than expected.
The solution is to fit a Compressor Bypass Valve either side of the turbo and luckily Bosch makes one that was used by Saab and Porsche etc:
It's vacuum operated so it should work off the same manifold connection as the old turbo's CBV.
Obviously you will have to modify the turbo inlet hose and turbo to intercooler hose to allow you to connect the CBV but you should return to smooth running without the noise of a BOV.
Just had a look and a used one is on sale here:
https://www.ebay.co.uk/itm/Turbo-Byp...MAAOSwnDpaFrb4