Since just before Christmas, their EFTPOS machine periodically goes into offline mode which is a huge inconvenience, as customers have to sign, and there is a long delay in getting the funds.
The ISP is Spark, who say that the Internet connection is fine. The EFTPOS vendor says the issue is probably something to do with the business network but haven't provided much help apart from that.
I'll take a look at the router config, check dynamic/static IP allocations for all devices, put some monitoring in place to see if the Internet connection is actually going down etc.
Is there anything EFTPOS terminal specific that I should look for?