Cruise Control = Engine Stall?? - Part 1 (Ram Cummins Diesel)

Don't see this weird symptom every day... This 2005 Dodge Ram Cummins Diesel runs great, EXCEPT when you try to SET the Cruise Control! When you touch the SET button, the truck momentarily loses power, surges, and comes back to life in 1 second. What could be the problem? Enjoy! Ivan