First off, a -.09 is fast not slow so I'm assuming you meant +.09.
Are you setting up the skier weight factor, Feather, Light, Nomal, XL befor you ski each person ? If its on no skier or too light it will show a slow first segment and then take off once it does the first calculation of speed.
To set the factors press on/off & up keys together, use menue to move up and down the list. Press the up key to bring up the b1, b3 ans b4 to exit settings. Increase the numbers for a fasrter segment.