hello

i am having trouble getting a spdif signal to my maudio 2496 card from a lucid ad9624 all i seem to get is a rather large crackling noise or no audio at all my meters are all lighting up with a decent signal on my hardware ,I have the clocks locked in maudio delta panel to external and the lucid set to the same sample rate on internal m audio panel says locked.
the audio im getting is just a large crackle or no audio at all

my set up is
dell 490 quad 1.86 12gb ram - maudio 2496 audio - line out- maudio bx5 monitors
rhodes mk60 + akai miniak - midiman mixer - art tps 2 - lucid ad 9624 - spdif out - maudio spdif in


do you have suggestion as what is causing this problem
software reaper 64 bit
pro tools m powered 8