When I writ on my Promethean board, my pen drags between letters and numbers. Basically, the pen is still writing when I pick up the pen.
For the issue you have described I would recommend contacting Promethean Technical Support directly for further troubleshooting to resolve the issue.
You can fill in the contact form on the link below:http://goo.gl/j3AT8SOr alternatively you can phone us and quote reference number 00498440. A full list of numbers can be found on the link below:http://www.prometheanworld.com/us/english/education/support/technical-support-numbers/ThanksAdamPromethean Technical Support