There is no datalink on the BS3000 aux port (pins 6 and 7 are not used):
As an alternative, maybe have a look at a Beolink Converter 1611 connected to the BS3000’s ML socket. You would need to investigate the Audio Aux Link input to the BL1611, or add an MCL2AV to use datalink. Have a read of this extensive thread to find out more: https://forum.beoworld.org/forums/topic/beolab-3500-and-1611-converter-settings/