Here's one method that is sure-fire.

1. Set up Maxis router as per usual, and then DISABLE wireless.

2. Set up any other router as per usual (you want the router to act as if it was connected to a device that served direct access to the Internet, which the Maxis router is doing. ASUS routers call this setting "Automatic IP". You must not attempt to connect via PPPoE or any other method that requires username/password).

3. Set the Maxis router to DMZ your custom router.

That's it. Remember to reboot your custom router once every 48 hours or so.

Somebody's said that if you turned your Maxis router into a bridge and used the (ASUS, in this case) custom router to log in via PPPoE, you can even put the ASTRO on the custom router, and you don't have to reboot the router every 48 hours. I haven't tried that; maybe I will one of these days and see what happens.

I don't have iptv but I'm running the Mikrotik rb951 as my main router off the ONU doing the ppoe login and supplying the wifi connectivity. The router is configured to pass the voip vlan info down to the Thomson box working as an adapter for voip only. I suppose the same principle should work for iptv?

Works fine.

BTU -> Technicolor (or Thompson) -> Asus RT-N66U -> switches for other network devices

1. Set up Maxis router as per usual, and then DISABLE wireless.
2. Set the Maxis router to DMZ your custom router on Port 2.
3. Connect Port 2 on Technicolor / Thompson to Asus WAN port.
4. Set-up the Asus first. Under Asus -> LAN -> IPTV, ensure the following is correct:

Select ISP Profile = None
Choose IPTV STB Port = Port 1 & 2
Use DHCP routes = Microsoft
Enable multicast routing (IGMP Proxy) = Enabled
Enable efficient multicast forwarding (IGMP Snooping) = Enabled
UDP Proxy(Udpxy) = 0

5. Set up the Asus to dial a PPPoE connection -> supply username and password.
6. Connect decoder LAN cables to Asus Port 1 and 2.
7. Connect switch (if any) to Asus Port 3.

That's it.

If u can if not using VoiP.