I just finished installing my 898cSI unit. I noticed that when I loaded the Humminbird PC onto my computer and registered my unit and logged on to Humminbirds web site that a updated soft ware version was available. I down loaded the 4.970 version on to a SD card as per the instructions. After the start up of the unit I noticed that the soft ware installed in the unit was 4.880 version. So I decided to install the newer version. I reset the defaults and powered the unit down ,installed the card on the left side slot,and powered the unit up. A window came up asking if I wanted to install the 4.970 version over the 4.880 one I said yes. Then a other window came up in red asking me if I was sure I wanted to replace the program I said yes. After the unit went into it's normal mode I powered it down,removed the SD card and started the unit back up. I checked the system screen to see if the up date took and it showed that the version 4.880 was still there NO update to 4.970. Could someone please tell me what I'm doing wrong.