Hi lgs131,

 I have a degree in electronics and I worked with computer and electronic systems for 22 years before a carpal tunnel surgery put me on this site with RSD in both arms,shoulders and mid back(it spread) . Let me try to explain how the medtronics SCS works. First your son has a remote control that he turns up and down the electical pulse to cover up his pain signal to the brain, inside his body are the leads that go into or close to the affected nerve(or where ever the Dr wants it.) Then the leads are attached to a miniature coil pack that makes the pulse and a tiny reostat that actually turns up and down the voltage(this is a one piece unit)...it is what the remote controls. I would want to check the reostat for sticking, it could be sticking on a low pulse and stays there when turned up and then could be breaking loose and go up to the high setting in an instant. Look at it like a dimmer switch on a ligh bulb. Another thing that could cause the irratic operation it the remote its self. If it were me I would have medtronics getting it diagnosed correctly or replaced. Your son knows how it is supposed to work, it is supposed to go up and down very smoothly...the voltage transition from low to high should be very consistant and smooth in operation. You should GOOGLE the Medtronics recall. Now, I am telling you what I would think and do, I am not a DR but I am very keen with electronics...I do not have an SCS and the problem your son is having is one of many reasons I dont. I know that when they work ....they work good. Have you ever had a TENS unit on a sore muscle? They work the same way as an SCS but they use a higher voltage, I have used one many times and the voltage transition from low to high is a very slow and consistant raise in voltage and you can feel it when it gets uncomfortable with out hitting you with a big charge all at once. Please do not consider what I wrote as a diagnosis but my own thoughts stemming from my electronics education and experiance. I read their recall on the bad leads, most of the problems came from a heart unit......not kewl! Here is the recall link for the medtronics leads http://www.medtronicheartleadrecall.com/?gclid=CNuQjrjJupMCFQoRswodGAmUCA