That musty smell could be coming from mold in the carpet and or it's padding, as basements tend to be damp. You could have the carpet cleaned professionally or clean it yourself with a good carpet cleaner. If this is unsuccessful it may be necessary to replace the carpet padding or both the carpet and it's padding.
Eva-dry EH-500F, will dry air and prevent formation of mold and fungi. This will help you in getting rid of musty smell from basement. For better result it is advisable to clean basement before installation of Eva-dry EH-500F. You can get Eva-dry EH-500F, with fragrance.
smell it! old original cards have an unmistakable musty basement smell that cannot be reproduced.
Vinegar
you wash it????
Buy a dehumidifier. Rent an ozone generator. Info on my site.
Kerosene smell car carpet
The musty smell of moisture and possible water marks would indicate that there is a problem with water.
You can either remove your carpet and add a new one, or wash the carpet
stick an air freshener in the interior vent
Go to a professional cleaning supplier and ask them. They have the knowledge and the products to do the job.
"The musty smell of the attic filled my nostrils" BWHAHAHAHAHAHAH
The first step to getting a musty smell out of a closed up house is to open the windows. You will also want to burn some candles. Spraying Lysol will also help get rid of the musty smell.