When it comes to upgrading your phones – Always get a second opinion – With the NBN, your old PABX phones don’t work…
This setup is what we like to call “sh*t!, Unreliable and only ever implemented by people who don’t really know what they’re doing or know of a better way but can’t be bothered” 
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Don’t let someone sell you this!! If you have 10 phones or less then just go to hosted voice, much easier, more reliable and cheaper total cost of ownership 
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