The led flash in the "digital input" module.i get nothing out. Since i don't have a digital input, but an analog input, i do not understand the meaning here. I thought the clock for what you call  "CPU  Steady Clock Control Remote Control" in 17)Block diagram, -  was related to the digital input connectors,  or -  like in my case the internal clock. And that this internal clock was from the same base as the clock fed to  all the digital circuits. But this must be wrong. I have now found out that when i connect ADAT IN to ADAT OUT, i get a signal on the output. From this i conclude that the clock has to be fed from input part to output part in the digital processing chain. When i look at the block diagram in the manual, it is not obvious. Is it only the DAC that does not have a clock if we do not connect ADAT IN to OUT, or is it some more blocks in your diagram?