Case tr 270 aux hydraulics acting up

Hi new here and while I found this place as I was searching for a solution to a problem I am impressed with what I found and decided to join, I hope to be accepted as a regular here but hopefully not just for problems! I just acquired a tr 270 case with 450 hrs and several implements, bucket loader, auger, brush cutter, etc. My problem is the aux hydraulics seem to "kick out" when I move the thumb wheel on the RH joystick in either direction, what I mean by "kick out" is that (with the brush cutter for instance) when the thumb wheel is initially engaged the cutter blades start spinning up normally with the hyd motor seeming to be getting full pressure and flow at first but before it reaches full speed it will suddenly lose hyd power and slow down almost to a stop. With he auger attached the same thing happens except that the auger will start out normally but then in a couple of seconds it will stop until the controls are reset but then the same sequence of events starts all over again same as with the brush cutter. So far I have tested and verified that there are no broken wires or open circuits in the joystick and while it is my understanding that is a common problem I was assured by the dealer that the problem had been dealt with on the newer machines like mine.