Setup is Vital Systems EC01 Master Controller, with RTELLIGENT RS750E Ethercat drives for X & Y, RS1000E Ethercat drive for Z.

I'm having a mapping issue on an Ethercat setup that I am bench testing before installing.

I have XY working fine independently but when I go to add the Z into the mix. The Y wants to drive it and the Z wants to drive Y simultaneously.
It's as if one is slaved to the other but they are not.
I have them indexed 1600, 1601, 1602 and 0x1a00, 0x1a01, 01xa02 for XYZ respectively on the RX PDO and TX PDO.
What am I missing.