Dodeca Hexa with “Flier OPTO ESC” – AUX Output Channels are not working correctly

I know that I have a very unique setup. But is this not what makes our hobby so interesting?

Before I start to explain the actual problem I like to share some of my details:

Frame Type: Dodeca Hexa (12 Motors)
Flight Controller: Cube Black (003E0028 33375100 37353832)
Firmware: ArdoCopter V3.6.6 (6b88b2ba) (I am not running the latest version because I had an issue with the compass calibration on V3.6.7)
System: ChibiOS: d2030d88
Software: Mission Planer 1.3.66
ESC: 12 x Flier Air (Opto)
Remote radio: Self build. Joysticks are converted via a ppm to pwm converter

Description of Connection:
As I am working with “Opto” ESC’s I have to power pin “7” of the FC (Cube 2.1) as per manual with 5V. What I did with a separate BEC.
6 ESC’s are connected to MAIN1 to MAIN6 the other 6 ESC’s are connected to AUX1 to AUX6.

Problem Description:
Before I powered pin “7” of the FC with 5V via a separate BEC the motors wasn’t working at all.
After powering pin “7” with 5V and performing a motor test I have the following effect:

Motor1 on MAIN1: Working perfect as expected
Motor2 on MAIN2: Working perfect as expected
Motor3 on MAIN3: Working perfect as expected
Motor4 on MAIN4: Working perfect as expected
Motor5 on MAIN5: Working perfect as expected
Motor6 on MAIN6: Working perfect as expected

Motor7 on AUX1: Do not respond at all
Motor8 on AUX2: Do not respond at all
Motor9 on AUX3: Motor no.9 should run, but Motor no.7 is running
Motor10 on AUX4: Motor no.10 should run, but Motor no.8 is running
Motor11 on AUX5: Motor no.11 should run, but Motor no.9 is running
Motor12 on AUX6: Motor no.12 should run, but Motor no.10 is running

I tested each Motor, ESC’s and the cabling by using a servo tester. With a servo tester all motors are working perfect as expected. Means: There are no faults in cabling, ESC’s or Motors.

I wonder if the AUX connections getting powered from the 5V I connected to pin “7”.

I hope somebody have an idea what could be wrong.

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