Maxis + Astro IPTV connection problem

TM modem + Thompson Router + AC1200G+(AP mode)
Astro Multicast function will be disrupted when I connect my Asus router to the Thompson LAN port

TM model + AC1200G+(router mode)
Astro multicast no connection at all.



Call up Astro, they said cannot use 3rd party router.
Asus replied also said not support Astro.

How lo?? bought this new router now cannot use..