DiGiCo SD9: Audio I/O, no sound from a rack and card conforming

Start in Setup → Audio I/O and separate connection, source selection and routing. A connected port and matching cards do not prove that the intended signal reaches the channel. Save a session revision and record the rack model, cards, SD9 software, sample rate and physical path before changing anything.

1. Select the rack port and compare Device Type and Connection with the equipment and connector in use. If the link uses DiGiCo CAT5 over RJ45, it carries MADI over CAT5: TN227 warns against treating it as Ethernet or inserting an Ethernet switch. Check the cable and connection against the exact rack documentation; the connector alone does not identify a D-Rack or D2-Rack.
2. Check Listen To Copied Audio and whether the session should monitor the stage or playback. This control lets you hear the MADI recording return through the original source channels; leaving it enabled when you expect live inputs changes what you hear. Record its state and compare sources during rehearsal, using agreed destinations and levels.
3. In Setup → Audio Sync, compare the selected source and sample rate with the system design. Getting Started B covers 48 and 96 kHz and notes that a green OK indicator can show a valid clock even when it is not the selected source. Do not select a different clock just because its indicator is green.
4. To distinguish the input socket from channel routing, Issue E documents Line Check: enable Line Check, select an input socket and use Listen to send it to the Solo assigned to Line Check. First check which output receives that Solo and the listening level. This function lets you hear an input even when it is not routed to a channel; check its availability in the installed software.
5. If you hear the source in Line Check but it does not reach the channel, check Main Input, port, socket and Main/Alt selection before rebuilding the rack configuration. If you cannot hear it in that check either, trace back through source, cable, rack, connection and synchronization. Change one variable at a time and record where the signal disappears. If the fault persists or returns, retain the file and screenshots for support; one recovery does not establish its cause.

Use conforming to match the cards defined in Audio I/O to the installed cards. In Issue E, Conform Rack affects the selected rack; Conform All Ports covers the entire console. If you are investigating a mismatch in one rack, identify that port and its cards first.

Default Rack has a different effect: it resets gains, pads, SRC and phantom-power settings for the selected port. Do not use it instead of conforming as an attempt to restore audio.

1. Save a new session revision and Audio I/O screenshots. Compare the session’s rack model, card order and card types with the connected rack; a show prepared for another configuration needs this check before passing signal.
2. Select the port and check Card/Slot Type. The manual shows green when the type matches and red when it does not. For one card, Cards & Sockets → conform card limits the action to that card; Conform Rack updates the selected rack. Schedule the change outside event operation and record its intended scope.
3. After conforming, compare the labels and recheck sockets, patch and destinations with a test signal. If they match but an output on a shared SD Rack is still unavailable, check its console assignment in the linked Optocore guide. Do not treat a red card-type name as equivalent to every other red system indicator.
4. If the result does not match the plan, stop testing and keep the before-and-after screenshots. Before returning to the saved session, check that it still matches the connected hardware; reloading a file does not undo physical installation changes.