OK thanks for the heads of where to look for the problem, in fact all I did was changed the above file as per DrBytes instructions and the JSON problem is no more, yay!
Now I get one final error at checkout page which is very cryptic but has nothing to do with JSON ... i think not anyhow here it is 'WARNING: An Error occurred, please refresh the page and try again.. that is at step 3 before being sent to the bank ... do you think it's related ?
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