1. Go to the  Currencies  tab and select  Change Default Currency  from the drop down;
  2. Click the radio button for the selected default currency; 
  3. Click  Save Default Currency.

You can have multiple currency accounts in an Ezyaccount. You nominate a default currency account when you register for an Ezyaccount. Any funds sent to your Ezyaccount without a matching currency account will be converted into your default currency.