Old Motorola HD-uDTA-M works, but new X1 TV box doesn't
We upgraded our service and I'm trying to replace an old Motorola HD-DTA100u set-top box with a new XiD-P (Pace PXD01ANI) box. The old box works fine, and going into the settings it shows signal strength is "good" -- apparently the two possibilities are "good" and "poor" and it does not show a numeric signal strength.
When I connect the new X1 TV box, I get error RDK-03036 and rebooting the box does nothing. Comcast sent us two of them, and I have tried both with the same results.
Cable comes in to an EVO-1-5-U/U powered splitter. The Xfinity modem is on the modem port, the DVR and TV box are on other ports. Internet works fine and the old (non-X1) DVR works fine. The new X1 DVR arrives tomorrow, so we'll see if that one connects.
Any ideas other than having an Xfinity tech come out?