Strange S/PDIF behaviour ... urgent help deeply appreciated

Hi! I am suddenly having trouble connecting a piece of outboard gear through S/PDIF (M One). I want ProTools to be master clock, and M One to slave so the Clock is set to Digital on M One. M One indicates that digital clock sync is in place. Then I have ProTools Playback engine->Other Options set on ADAT and S/PDIF mirroring disabled (since I use the ordinary S/PDIF connectors and also do not want my S/PDIF to sound in my analog 1-2. S/PDIF Compatibiliy is set to Other. Sync Mode is set to Internal (ProTools is master). I have an audiotrack with a send to Optical 1-2. I have an aux input track with input on Optical 1-2 and output to analog1-2. This is the setup I have determined to use from the manuals and the DUC search. However, I cannot get any sound in to M One. The only way I can get the send to sound in M One is to have ProTools using the mirror analog 1-2 and use those in the sends and inputs (with the problems having the singal mirrored to analog 1-2). Am I doing something completely wrong here? Any hints deeply appreciated. Cheers, // JW

Please, does anybody out there have time to help me out? // JW

The problem is probably that if you want to send a S/Pdif(two channel) signal through the optical port, you need to switch the optical format to S/Pdif instead of ADAT(8 channel). Then disable mirroring and you should be set.

Hi! If I select S/PDIF as Optical Format I have no available i/o outputs other than analog 1-2. If I also disable S/PDIF mirroring under optical format I can (as with the other method described above) bus the signal to out on optical 1-2, M One shows signal. However, the signal is not coming back in again on optical 1.2. I know the connections are right on M One (digital i/o setup). And the signal is being routed PT->M One->PT if a use SPD/F mirrored to analog1-2 -> M One -> S/PDIF in. But that is not the way it should be. Just shows here that cabelling and connections are ok. What is wrong here ? Cheers, // JW

Try going to the I/O setups and reset the settings to defaults. Things may not be working on the surface because they are not routed internally the way you think they should be.

I found it. If you change the Optical Input format to S/PDIF (Setups-Playback Engine- Other Options dialog box) and assign an input on a track to the optical S/PDIF input port, you will not be able to use the RCA-based S/PDIF input port on the back of 001. The S/PDIF (RCA) input port and the optical input port share the same S/PDIF receiver chip and can't be used simultaneously. This limitation only applies to input. You may use both the S/PDIF (RCA) and Optical outputs simultaneously, however be aware that they will mirror the same audio data (they cannot be addressed discretely. Thanks, many posts on this. And I'd like to add to the above the tip also by a DUC user above. VERY IMPORTANT -> Go inte I/O settings and click default when changing the Setups-Playback Engine- Other Options, EVERY TIME. And today I am not even tired :-) Cheeers, //JW