about a month ago i had to take the car into town and parked in william st northbridge got a ticket from a ticket machine on the street and noticed the clock was about 12 minutes out in there favor so as i walked up william street i looked at the clocks on other machines and they all had diffrent times on them they vared about 15 minutes so could pay for half an hour come back and you have a ticket for over parking so watch that when you get a ticket from those ticket machines