George;
Noise is a difficult topic. There are some techniques that migh help you to reduce the noise level of the data acquired.
There is a good application note that you can find from at Web site which talks about that. The name of the App Note is "Field Wiring and Noise Considerations for Analog Signals". To download that one, go to www.ni.com and type in +field +wire at the search field.
Hope this helps.
Filipe