Don't know if this thread is dead, but I have been struggling with ShowMax streaming to my Chromecast for the last month. The issue is buffering and frank desync between casting device and the chromecast. This happens if I try to cast from my Motorola Nexus 6, my Samsung Galaxy Note 3, my Chrome browser on my Windows 10 PC as well as from my Thosiba Chromebook 2. Also when I try to watch Showmax on my PC or Chromebook it buffers endlessly (never stops until I press on any point along the scroll bar). The pressing on the scroll bar is also the solution when I'm casting, because then the streaming resumes (at the point where I selected). IF I watch Showmax on either of my two android phones then I don't have any buffering issues. All my other streaming services works fine, even when casting from all the mentioned sources. I have a 20Mbps fibre line with Snowball as my ISP. Showmax is very unhelpful, with their only advice so far being "reset your router and chromcast". Both those solutions doesn't work. The service is thus so unusable that I'm considering terminating my subscription.