Strange behaviour of axis 4 and missing 90 degrees of axis 5

Hey,

I am struggling with a few of my problems:

The robot is AR3 modified to AR4 (teensy 4.1, teensy4.1 program with cui encoders, plus endstops I modified for inductive sensors).

The encoders in these videos are disabled.

In the program I changed the lines through the inductive sensors (to align the axes.)::

//degrees from limit switch to offset calibration

float J1calBaseOff = -1;

float J2calBaseOff = -13.1;

float J3calBaseOff = 10.4;

float J4calBaseOff = -1.5;

float J5calBaseOff = 87;

float J6calBaseOff = 17;

float TRcalBaseOff = 0;

My problems are the strange behaviour of axis 4 when driving axis X. Is this rotation normal?

The second problem is that the gripper is not kept parallel to the base. Additionally, axis 5 after axis calibration has an angle of 0 degrees. When I go to 90 degrees (as in the video) it has about 92~3 degrees. Is the value of steps per degreee incorrect?

And how can it be calculated? The controller's microstep settings are as in the manual.

Third problem is this humming sound of axis 4 stepper motor. After connecting it to another controller (TMC2208, TMC2209, DRV8825) it does not make this sound. (But this is the smallest problem).