The problem is not with your music but with how you market yourself online. It has a lot to do with the search engines and how people find you. I have learnt a little about internet marketing, and the success rule is, post everyday for ninety days and you will start to see amazing results. Set up a blog and talk about your music with links to your audios, and where people can buy them. Use popular keywords and learn about backlinks. I hope this will help you increase your sales. Good Luck!