Put them in a baggie with some coffee grounds. The coffee grounds will absorb the odor. I bought a Featherweight that had a terrible stinky carrying case. A friend said to use coffee. I put a small topless container in the top and amazingly the musty smell is gone. I have left the container in the case and just put it aside when using the Featherweight.
The coffee also got sprinkled in the back of our car because someones cat got in there and did something that made the car unbearable to be in. It even took away that odor.
Believe an old wife anyday!!