New box--Error Code RDK 03004

New TV customer, had box delivered today.  Connected coax cable from the wall to splitter that came with equipment, then one coax from splitter to X1 box and another coax from splitter to cable mode,m.  When all 3 are connected I get the error code RDK 03004 and it asks to check all connections.  They are fully secured on all ends.  I then ran just the coax from the wall plate to the X1 box, it completed the setup but then stated no internet connection and wouldn't allow to pull up the guide or change channel.  Unhooked it from wall and tried again with all 3 hooked up to the splitter, same RDK 03004 error.  My internet service is fine and no loss of signal or service when it's connected to the splitter.  I also have a network cable going from my cable modem to the network port on the X1 box.  I've read that possibly getting an amp could help this issue, any suggestions?