In my previous job I heard many Australian speakers using aye like sorry and pardon to ask for repeating what other person said. I also heard one kiwi guy using aye in the same way. But, now I work somewhere else with people from different countries -- although they speak English. They mostly use huh instead of aye and don't understand aye, although most of them were born in Australia.
So, does aye really mean same sorry and pardon in Australia and New Zealand?