Topic: HDSP AES 32 and Tascam DM 4800 problem

Hi Im trying to connect my hdsp aes-32 card to the tascam dm 4800 with its optional IF-AE/DM card.The problem is that at the rme settings it says: Word No Lock
                       AES 1 no Lock
                       AES 2 no Lock
                       AES 3 no Lock
and so on.
Is there any specific action i should perform?At the clock source it has 3 options: Internal - Word Clock - AES.I assume that AES is the correct option but stll there is no lock.
Moreover I tried using bnc cable with the rme as a master and the tascam set to slave and there was the same message in the settings dialogue:Word No Lock
                       AES 1 no Lock
                       AES 2 no Lock
                       AES 3 no Lock
but in this instance when i tried changing the sample rate in the rme settings the tascam followed.But again no audio.
I appreciate any help:(
Thanks