All three of my Chomecasts sucked down a steady 450Kb/sec of data from Dec 12 to Dec 19 (and similarly, at a slightly lower data rate, in an earlier period from Dec 3 to Dec 6). They aren't doing it any more, and didn't do it during any other intervals in the 30 days I have detailed logs for. I can see this in the detailed per-client bandwidth usage charts on my wifi AP (a Meraki), and I can see the aggregate inbound bandwidth usage in the logs on my edge router. The total inbound data transfer to the three devices was over 15GB/day. (Before anyone suggests that I left all three Chromecasts streaming Netflix or something for six days -- no, I didn't. They were idle most of that time). Has anyone else seen this? Anyone have an explanation?