Telstra Smart Modem wont work with switch attached

[Titancom]

I received a new Telstra smart modem yesterday and took 1 hour for 2 PC's and NAS box to work with it, worst thing I have ever had to deal with but when I connect my managed GB switch to it everything drops offline and at one point this thing rebooted for no reason. Had Telstra support on the mobile while trying to get this weird thing to work with normal devices but in the end, the modem\router won't accept the switch without having a dummy spit and dropping everything. They had no idea how to get this to work with it and said call premium service haha what a joke. Anyone had this issue and figured out if this thing will work with a managed GB switch or not?

[Titancom]

OK from lots of searching I think what I will need to do is either:
1: change the modem IP range to match the switch being 192.168.1.1 range or
2: change the switch to not assign IP addresses and hope the modem assigns them properly through to all devices connected to the switch

[MattyC]

Appreciate your patience in this. How'd you get on with it? I'd like to know that got you up and running. - Matthew.

[Titancom]

In the end, I had to fully reconfigure the switch and NAS box to get them to work normally again. The switch I had to statically set it as 192.160.0.2 and the NAS box which has 4 LAN connections I had statically set them in the high range of the 192. range and eventually got it all working, connected the switch via its port 1 to the new Telstra smart modem port.