10k Pot for Stepper Motor control.

I have a 10k ohm pot connected to GND and 5V and the wiper connected to pin 1 on a Ardiuno Uno. There is a LCD that reads the pot. As i rotate the pot from zero the motor starts moving but instead of increasing speed smoothly as I increase the pot it makes small jumps in speed and at 25% of the pot the motor jumps to full speed and remained there as the pot is increased to full. Others have built the same project that I am building and only one has experienced this problem. Could it be a bad Arduino. I have tried two pot on the Arduino and the both act the same.
Thanks

connected to pin 1

Pin 1 or to pin A1?
Pin 1 is a digital pin, it will read as a low for <= 0.9, read as a high for >= 3V, and could go either way in between.

A1 give readings from 0 to 1023, smoothness will depend on the quality of your pot.