A client rang us up yesterday, and it started to look like another outage, we are all going not another outage.
It turned out that it was actually user avoidable, the old EFTPOS units use the same telephone line as telephone handsets, as such, they need to be updated when the NBN took over, this was the problem.
So when you get a letter from the NBN, you need to contact your EFTPOS provider to check whether their unit will be affected by the switch over to the NBN and if you are going to get an updated EFTPOS reader make sure that it is a new model reader like this one.