Help!

I purchased a used VM17 and when the machine turns on, after the homing sequence, I go to do a tool change and the spindle height to match the carousel is off. It can be from a 1/4" to 3/4" high or low.

I then have to go into F7 Parameters..... F4 Axis.... To "Tool Change" and adjust the Z# to move the spindle to the correct height. Anyone know of another setting in the machine I'm unaware of needing to be set to avoid this?

The indicators for the Z limit switch shows it works. The value for Z is different after every homing cycle.

In the words of Slim Pickens in Blazing Saddles, "I am deepressed..." Help!