Comment # 8 on bug 75491 from Eric Grüttefien

> Maybe they are too cheap and don't properly connect the ddc wires or pull
> the right pins down. 

I've open one cable you seem be right. DDC alias AUX CH+/- seems not to be
connected. 

Cable Adaptor Detect alias Config 1 I' have still to check.

They are passive ones using a NPX/Phillips PTN3361B level shifter.

I will fix the cable and report back.

Thank you very much for the hint.