RCA to Beolab cable and its power adapter

I lost a small power adapter used with a RCA-to-B&O cable (running it with Beolab2/Beolab3 active speakers).

Here is the photo of the cable requiring that power adapter:
As I understand this power adapter supplies a continues voltage to the cable keeping Beolab speakers alive (triggering them from falling asleep). Without it Beolabs are always in sleeping mode.

I would appreciate if you suggest how to get a replacement to the lost power adapter.

Here is the diagram I found on Internet showing a very similar cable (except my cable has a female power adapter jack, while the one on diagram is male).

I would contact Sounds Heavenly http://soundsheavenly.com, they should be able to help you.