Promotion voucher being applied twice to cart

Hi

I think I am experiencing the same problem as Mike here:

https://forum.grabaperch.com/forum/11-21-2016-mis-calculated-discount

It appears to happen when a customer applies a voucher to a cart and then subsquently adds another item to the cart.

Interestingly, if you make the Maximum discount the same or less than as the discount amount the voucher doesn't get applied twice. If the limit is any other amount (or blank) then the discount is applied twice.

Screenshot below shows the discount that should be applying £10 to the cart total.

I am also getting the rounding issue with the voucher when applied pre-tax (VAT in my case). Entering £8.33333333 for a £10 voucher sometimes calculates at 9.99.

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    App runtimes: <?php $apps_list = [ 'perch_mailchimp', 'perch_members', 'perch_shop', ];
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    PERCH_CORE: /Users/ellimondo/Dropbox/Sites/ellipress/dev.ellipress.co.uk/perch/core
    PERCH_RESFILEPATH: /Users/ellimondo/Dropbox/Sites/ellipress/dev.ellipress.co.uk/perch/resources
    Image manipulation: GD
    PHP limits: Max upload 32M, Max POST 32M, Memory: 128M, Total max file upload: 32M
    F1: 0c66c2e1f82f9e0b7617b2cb8270f2c7
    Resource folder writeable: Yes
    HTTP_HOST: dev.ellipress.co.uk
    DOCUMENT_ROOT: /Users/ellimondo/Dropbox/Sites/ellipress/dev.ellipress.co.uk
    REQUEST_URI: /perch/core/settings/diagnostics/
    SCRIPT_NAME: /perch/core/settings/diagnostics/index.php