x axis ramdomly decides up is down (1 reply)

I am working with a homebuilt delta printer. Using ramps 1.4 on arduino mega for controls.

Here's the problem. Sometimes the x axis decides that to move the carriage up it needs to go down. I am using Repetier as a host program. I go to the manual panel and hit up. Y & Z do the normal thing X goes down pushing the effecter way off to the side in a hurry.

The crazy thing is, when I command the effector to go down, everything is normal. It goes down as needed. Sometimes with a complete power down of printer and a reset of the arduino I can correct this but it is not always successful.

Can anybody help out with this. Am getting very frustrated here. The problem began a few days ago. I thought something was just messed up with my firmware. I went back to Repetier and made a complete new firmware using the latest development edition. I flashed epprom and everything to fix the problem. It looked good for about a day then it started bugging out again. I have even tried reversing the plug on the ramps. This worked the first time I hit home. The axis went up as it should. Then it decided to be drunk again right away and function opposite of what it should.

Jonathan