On several occasions, I have purchased a pack of 10 or 20 Sterling cigarettes from Dobbs General Store. When I light a cigarette, it doesn't always puff. After several attempts to get a 'drag' from the cigarette, I notice the filter of the cigarette goes a dark brown, nearly black colour. The cigarette gradually gives me a few puffs, with some effort might I add. The cigarette doesn't go out but barely gives off any smoke. I smoke Sterling Kingsize, the red version. What could the problem be? I have purchased a substantial amount of packets the product, given it is my first choice of cigarette. My name is Mr Ryan Woollard. Telephone: 075531212731. Email: [email protected].