Not sure, but try to set IGMP v2. If you have DoS protection enabled, try to disable it for a while and test. When changing wireless settings reboot the router to ensure wireless devices have been...

NCSI is a Network Connection Status Indicator which is used to determine weather the device has an Internet access or not. Do you have any wired clients that are connected to the TD-W9970 ? (computer...

@Robinson_Chera Disable QoS and set these wireless settings, then test if that helps. For 2.4 GHz band: For 5 GHz band:

I've updated my previous post, follow the directions and get back if you observe anything abnormal in device's logs.

@paulcanning According to the screenshots you've sent, you have VDS/ADSL router TD-W9970 HW v4 (not Archer C50): Here's your user guide. Here's your internet connection settings: Make sure your...

@paulcanning They are not too much, the router will handle these for sure. On the bottom of the device there's a sticker with information. Can you check what's the HW revision of that device ? You...