Follow this article, if the issue persists you may want to call apple or take it into an Apple Retail Store.
Hope this helps.
1800 MY APPLE
apple.com/retail to set an appt.
Hi and thank you for responding. When I used the Nike+, it worked perfectly. However, I got a new Nano and now I am only using the built in accelerometer included in the latest OS update on my Nano, which does not require the dongle and device in my shoe.
This is where I'm having issues, and I am planning to bring the Nano to my local Apple store to see what they might suggest. In speaking with my trainer, she mentioned that those built in accelerometers are not very accurate, so I may be out of luck and may just have to use a Garmin or other device that is more accurate. Again, many thanks.