Considering that both the system and the train are from Alstom and are
designed for up to 100 km/h (regardless of what operating speed options
other cities might adopt), I don't think that this would be the issue. I've
learnt from observing many new tram systems and their vehicles over the
years that you need to allow up to a year, sometimes even more, for
everything to bed in, faults to be identified and rectified. By six months
everything should be running pretty sweet but issues may be uncovered
beyond that. This is completely new technology for passenger transport in
Australia and both operators and passengers have to become properly
familiar with it. Give it time.

Tony P