First of all, your home seems to be wired not in the traditional way for cable TV. Usually, you'll have 1 coaxial cable coming in from the outside demarcation box into your home. This cable is then hooked up to a splitter and then individual coaxial cables run to each outlet in your home. See...
I don't know if anyone else has this bug, but when IPV6 is enabled on my router, Time Capsule does not work. My mac is unable to find the backup disk. Everything works fine once IPV6 is disabled on the router.
This is on a TM-AC1900 (or RT-AC68U) running Merlin 376.48.