The Tappecue runs on a 2.4GHz network.  The default settings of the Time Capsule is set for both 5GHz and 2.4GHz in one network.  It's best to use the functionality of the time capsule that allows two separate networks, a 2.4GHz and a separate 5GHz instead of trying to use the combined functionality in one network. Then use the 2.4GHz SSID (wireless name) to connect to the Tappecue.