Arcadyan LH1000 - Voip registration issue.

[Tysong]

Hi there, 

I have recently been swapped over to a Arcadyan LH1000 smart modem gen 2 and cable adaptor, from my previous CG3100D due to service problems in the area. I am on naked cable, so do not have a copper line or a phone line with Telstra. 

The LH1000 does not seem to support 3rd party VOIP providers, and my gigaset C610A having a "registration at provider failed" due to the Arcadyan LH1000 blocking the SIP traffic.  Did not have this issue previously on the CG3100. 

I have been through the settings on the LH1000, and there does not appear to be a fix.  there is no SIP ALG setting in the firewall, and it will not allow me to port forward port 5060. 

If i plug my IP phone or router directly into the cable adaptor, it registers without an issue, but i loose the mobile network backup that the LH1000 gives me. 

Any suggestions on a fix here 

[cf4]

Have you tried putting phone in DMZ (Advanced > Firewall > Firewall)?

If that doesn’t work you could buy a second hand Telstra Smart Modem Gen 1.0 (Telstra Gateway Frontier) or Telstra Smart Modem Gen 1.1 (Telstra Smart Modem). I know that VOIP phones work with those modems and I have seen them on sale for as little as $5. Both have 4G backup.