DiGiCo SD12: MGB recording and DQ Rack control

If all 64 inputs are already available in Pro Tools, start with the second MADI path and its patch. In 64/32 mode, each MGB port carries up to 32 channels at 96 kHz, so 64 signals need both ports. At 48 kHz, the capacity per port is different: check the session sample rate before moving cables.

Separate the number of inputs listed in the software from the number of signals reaching it. Creating a track does not prove that a source has been assigned to it.

1. Save the console show and recording session. Note the sample rate, 56/64 format, SMUX/Hi-Speed framing, ports and destination of each channel block. Check whether SD12 MADI1 and MADI2 are available: if they already connect the stage rack, review the system design and installed cards before allocating them to MGB.
2. For direct recording at 96 kHz in 64-channel mode, check SD12 MADI1 OUT → MGB MADI1 IN and SD12 MADI2 OUT → MGB MADI2 IN. Each connection carries a block of 32 signals. If playback to the console is also required, add the two MGB OUT → SD12 IN return connections according to the patch; this bidirectional arrangement uses four BNC cables. Do not add unnecessary returns while troubleshooting.
3. Open the MGB Hardware Control Panel. Under MADI Options → MADI Port Settings, check that both ports use 64/32 channels for a MADI64 link. The 56/28 mode has a different capacity. On the Clock page, compare SAMPLE RATE MODE —High-Speed or SMUX— with the SD12 output; also check Current Clock Source and Status.
4. Test one identifiable source at a time on channels 1, 32, 33 and 64. Check the MGB MADI1 and MADI2 link LEDs and record which track receives each source. If only 33–64 fail, follow the second cable, its connectors, the console output and that block of the patch. A green LED confirms a link; an audio test verifies the channel mapping.
5. If the second block reaches MGB but not Pro Tools, check the route from the SoundGrid host to the SoundGrid ASIO/Core Audio driver. The manual specifies selecting Waves SoundGrid as the DAW audio engine and routing its inputs and outputs; the exact menu depends on the Pro Tools version. If inputs are missing from the list, identify the driver version and configuration before treating the issue as missing MADI audio.
6. During rehearsal, change one connection or setting per test and listen to the recorded file. Restore the initial patch if a test makes the result worse. Testing 1/32/33/64 locates a missing block; then verify every track required for the show.

Check whether control data is reaching the rack and identify the card/software combination. Dante audio, clock-leader selection and preamp control are separate functions. On the DQ Rack, Link reads OK when control data is received and NO CTRL when it is not; this display is not a switch for enabling gain control.

DiGiCo Reference Issue E documents DQ control through DMI-DANTE64@96. Describing a card as “Dante 64” is not enough to identify it: record the full model and both its DiGiCo and Dante firmware versions.

1. Read the rack identification, installed card, SD12 software version and both card firmware versions. The console has two DMI slots: identify the card in each slot. Check labels and documentation; do not insert or remove a DMI card while the console is powered on.
2. On the DQ Rack display, record Link, SR and Mode. In Network Menu, check Primary/Secondary and IP information. NO CTRL with audio present calls for checking the control path; do not change the Dante clock leader as an assumed fix for gain control. Status Menu is read-only and does not change settings.
3. In SD12 Setup → Audio I/O, check the DMI port, Connection and Device Type. Issue E shows DMI DANTE64 for DQ. Then use Dante Controller to check which physical rack socket feeds the card channel: renaming a channel does not change its subscription or identify a different preamp.
4. Compare the complete system with its compatibility documentation. Issue E specifies V1455+ for DQ, DiGiCo firmware v103 and Dante 4.0.20; the earlier DQ Issue A manual states V1454+. Record this difference and confirm the applicable package before updating. TN535 covers a different situation involving A168D/A164D: do not apply its rollback procedure to DQ without specific documentation.
5. To distinguish a console problem from rack discovery or control, prepare a check with DiGiCo Dante Rack Utility V2.1.0 on Windows. TN515 requires the PC and rack to be on the same network and IP range. Select the DQ under Detected Devices, check its name/model/firmware and observe the controls without changing gain, pad or 48V while another console is running the show. If the rack is absent, check discovery and the network first; if it appears, record that result and continue investigating the SD12 configuration.
6. Once control is available again, agree who owns the preamps and test one socket during rehearsal, with the destination at a safe level and the starting value recorded. Restore that value afterward. Enable phantom power only when the connected equipment requires it; do not toggle 48V to test communication. The cited Rack Utility version controls DQ but does not update its firmware.