The slave clock out (not the word clock out) of the ADAT Interface must be connected to the slave clock in of the 882 I/O. Connect the slave clock out of the 882 I/O to the slave clock in of the ADAT Interface.Connect the longer 50-pin cable from the Disk I/O to the "Computer 1" port of the ADAT Interface. Connect the smaller 50-pin cable from the ADAT Interface port labled "Peripheral 1" to the 50 pin connector on the back of the 882 I/O. Make sure the switch next to peripheral 1, labeled "4/8", is pushed in.Connect the 9-pin sync cable from Sync Out of the ADAT Interface to Sync In of the ADAT. Likewise, connect the other 9- pin sync cable to the Sync Out of the ADAT to the Sync In of the ADAT Interface. Be sure to check the sync ports on the back of the ADAT for proper connection. (There is a third port in the back labled "Meter Bridge" which looks identical to the sync ports.) Next connect the optical cables between the ADAT and ADAT Interface -- In to Out, Out to In.It's very important to follow this power-up procedure:1) ADAT (set ADAT to Internal sync)2) ADAT Interface3) 882 I/OOnce the ADAT Interface is properly configured for MIDI, go ahead and launch Pro Tools and enable ADAT Interface in the peripherals menu.