I had a musty smell in my basement, I used moth balls and it took the musty smell away with in the week. I still leave a few moth balls here and there in the basement to prevent the musty smell in the future.
I use Febreeze. Just spray in carpet, curtains and furniture.
There can be many reasons for your home to smell musty. The prime reason is Humidity and moisture that is why musty smell is experienced in the basements. You can put vinegar in open container for some days, that is likely to cure the smell. If its a basement, you can use a bag of charcoal and change it every 6 months. There might also be problems with your airconditioning system that is causing the problem so better get it checked as well. For details see the link below: