OP has your car been setup recently? If the chip is unknown switch it for an off the shelf calibrated to spec version stg1 and see if you get a difference.
My l6 does have a miss/hesitant point @1600 rpm 2which improved after a setup but didnt cure it completely.
also i do have a small black sootyness around the exhaust primary part , its minimal but annoying and I sometimes wonder if this could cause a small 'glitch' in small throttle slow driving.
A live map for any setup surely though is required to get the very best from what you have.