Shark Performance In Scotland
Dont use 3M polish either as its full of fillers so defeats the idea of detailing and getting it perfect. Black is the colour to iron out your technique so I would slow down a little and try and find the ideal combo......if its buffer trail then its your technique.
Try Sonax Perfect Finish and see if this makes a difference
Scotlands Shark Performance dealer and vehicle detailer - www.brotek.co.uk
Angelwax - BBS - Bilstein - Eibach - H&R - Loba - Milltek - VCDS