Does this refer to the cable that is connected between the control speaker (the one with the volume) and the woofer?
This would be an RS 232 cable and not a VGA RS232 cable, e.g. Roline RS232 BU-BU (1.80 m, VGA)

Thank you, but that is exactly the topic. Not every VGA cable can be used. VGA cables are actually there for image transmission and not for audio. But apparently there are special cables that can do that. And that's exactly the cable I'm asking about...

Enter "VGA extension 2m" into Amazon or Google and you should see extensions as required.

Sorry I can't help. I moved back to London in 2022 and these speakers are still in their original boxes, due to lack of space here.