Amazon FBA refunds

Is there a way to stop amazon refunding all customers without asking for the item back?

I get maybe 5 refunds a month, and none of them seem to return any products except the odd one here and there. They are all offered full refund which is taken from my account, NOT offered by amazon.

Lots of these are quite clearly from scam or competitors where i am also fighting for reviews to constantly be removed that are talking about items that aren't even what i am selling.

But is there a way to make it so that amazon dont give people the refunds until they return the item or until they post the item. Too many people just after free stuff and its costing me a lot of money.