Ok guys. Hoping someone else has experienced a similar situation or at least can point me in the right direction. I at first though I had gotten bad gas and this was pre-detonation but the car doesn't run rough at all and there are no other issues apart from a random thing where it will stumble right after start up and nearly stall. (The issue on start up has been occurring off and on when cold for months now) I honestly really don't know what this sound is but to me it sounds like an exhaust leak or a lifter or possibly timing chain? The only odd thing about it is that when sitting in park the sound is gone and it disappears above 2k rpm.
https://youtube.com/shorts/2OojwEYp6SM?feature=share
https://youtube.com/shorts/O8iSyk7JEzc?feature=share
Forgot to mention earlier this is a xDrive 35i.