Grbl CNC Router Troubleshooting

[Jeff_W]

Hey all, hoping to pick the brain here for some input-

I recently updated my GRBL shield to 0.9j, and now my z-axis behaves somewhat erratically. It will sort of randomly reverse direction when issued a g code through UGCS. For example, if sent a G00 Z-1 F25 it will occasionally move in the positive direction instead of negative.

I've been trying to set up homing and a touch probe just so you have an idea what pins and settings I've been tinkering with. In addition, when the Z axis behaves and I try to home it, it tends to hit my homing switch and stop and buzz. I've played with the debounce setting without much luck.

Cheers,

Jeff