I develop an application called RussCapture. Have discovered the same problem. A 14.1 laptop does not reduce dB, 14.2 mini does. I have changed audio device settings used by assetWriter and none that I have tried solve the problem. Don't know where to go next other than just hope it fixes itself.

I have this problem trying to use and record the "Large" presenter overlay in my screencapturekit app RussCapture. Selecting the large overlay creates a "Loading" folder that is empty in the app Tmp folder. Changing video output adapter settings does not solve the problem. I believe I have tried them all.

Are you using AVAssetWriterInputPixelBufferAdaptor? I was not using the identical output settings for both AVAssetWriterInput and AVAssetWriterInputPixelBufferAdaptor "attributes". Correcting this solved the problem.

videosettings and attributes are not identical dictionaries. I solved a similar problem by using the same dictionary for both variables.