I have a Samsung S2 VE (2016 model) running stock Android 6.0.1.

When on a Skype call, the call can last for between a few minutes and over 1/2 an hour but eventually the video freezes and a few seconds later I get a message on the screen saying "Connected to [network SSID]"

It seems others have experienced this issue with various models of Samsung. At this point I do not have any reason to believe it is a access point issue. The AP is a Draytek AP800.

I experience this even when using the tablet a a few metres away from the access point and the signal is good according to Net Info Pro.