it seems like you have an HXD serie recorder that have a known bug forgotting all the new tuning every time you switch it off (so every time it recognize the same new channel). If this is the case, be sure you have the latest fw (1.24 for HXDx90 or 1.70 for HXDx70), than proceed with an hardware reset (push stop and power off button together on the deck), unplug from main for 2 minutes and go through the easy setup procedure retuning all the channell.