Update: attempted replacing the ntp-7100 and still didn't work, possibly my soldering. Oh well, worth a go! Perhaps more practise needed.
Anyway picked up a cheap replacement board, £14. For that price I thought it easier and quicker than further troubleshooting which may have led to a bad uc ic anyway.
p.s. that was a damn good price for one of those boards, all others are extortionately high!
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