Hi!
Contrary to illico which uses a continuous video stream through a coaxial signal, Helix uses IP TV which works in a similar was as streaming Video on the internet. Because of this, each terminal will make a request to the server to access the content instead of hooking on a continuous stream. Depending on multiple factors linked to this way to access the content, there can be a delay in the playback between each terminal of a same home.
Hope this answers your question! 🙂