Hi Patrick,
I would recommend contacting Promethean Technical Support directly to help assist with the spiking issues you are experiencing so we can helpfully diagnose what could be the cause of this.
Please fill in the form below or click the link for the technical support numbers.
The form can be found here: http://goo.gl/j3AT8S
A list of support numbers can be found here: www.prometheanworld.com/.../technical-support-numbers
I have created a case to help support this issue, should you contact us directly please quote the case number: 00457235.
Adam
Promethean Technical Support