Takk for svar! Fant også dette svaret på TC Electronic som har laget elektronikken i høyttalerene:
Unless your S/PDIF transmitter uses the 4 aux data bits for something else than audio (which is very unusual today), the problem from going S/PDIF to AES/EBU is typically electrical.
The best solution is to use an active balanced digital line driver close to the S/PDIF output, and 110 ohm cable onwards, but for short term setups, you may get by more easily: A 75 ohm cable with a RCA phono type of connector in one end directly into a XLR male plug wired like shown on the drawing below..
Because of the low level and unbalanced output signal, the cable should be kept short (less than around 5 meter).