So.... I connected a coax from the ONT to a splitter, then directly to the router and the STB. No go.
TV guide still isn't working and any other data connection required feature on the STB (Message Center, Pay per view stuff, On demand, Widgets, etc).
Is it possible that the issue is on Verizon's end? Whenever I contact customer support, they keep telling me it's a bad STB... (This is my third replacement...)
