Checkout button has a delay before it's clickable

[GerryH]

I have a store I'm working on where the checkout button seems to not be clickable for about 10 seconds.

On inspecting of the element, it seems for about 10 seconds, the disabled tag is added to the button. Once it's removed, it works. I can't figure out what's causing it to have that 10 second period where it has the disabled tag. The paypal button seems fine.

store url is https://honibe.co.uk