I think its your scalp produce that smell.Smelly scalp syndrome occurs when there is an increase in microbial growth on the scalp. This is caused by excessive oils in the hair or on the scalp. The microorganisms thrive on the oil, and emanate on odor that is described as muggy, pungent and moldy. Smelly scalp can also be caused by environmental factors. For example if you live or work in a smoky environment, or one with many chemicals, that can contribute to a smelly scalp.I havent try rosemary and lavender oil,thats maybe perfect for hair.If you're using baking soda let it soak for 30minutes then rinse very well i suggest 1/2 cup baking soda to 3/4 gallon of water (add 10 drops of teatree oil it help killing bacteria)then after rinse make 1part of apple cider vinegar to 10 part of water pour to your head then wrap your dread with towel when its still soaking.Wait for 20 mins then rinse you can stand for 1week without "Stinky".Hope it work with you goodluck!