User manual

Appendix 3 – Upgrading the DUA II Firmware

All registered DUA II users will be contacted by Merging in the event of a DUA II firmware upgrade. This upgrade

can be performed easily in the field. If you are unsure on how to perform this procedure, please contact Merging.

• Disconnect the power supply cable,

• Remove the top cover,

• Locate the Flash ROM chip (It is labeled with a sticker “V 1.0”. This number may be different to reflect the

firmware version currently installed in your DUA II unit),

• Using a small screwdriver, remove carefully the Flash ROM chip from its socket,

• Take the new Flash ROM chip and plug it in the socket (by hand), in place of the old one,

• Take care to ensure that the new Flash ROM chip is inserted in the same orientation as the previous chip,

• Replace the top cover.

Appendix 4 – Troubleshooting / FAQ

Monitor LED is constantly blinking:

This problem happens when the DUA II has detected the selected sync source as active but cannot lock to it.

In this situation, all inputs and outputs are muted.

The most common occurrence for this situation to happen is whenever the DUA II and the equipment to which it is

connected are both set to slave to each other. This is a pretty common user setup problem. Care should be taken in

any digital audio studio to always set one (and only one) unit as the master while programming all other units to slave

to this “master” clock.

Note that while detecting the sample rate of the selected sync source, when set in AutoDetect SR mode, the DUA II

mutes also all its inputs and outputs and so the monitor LED is blinking.

Monitor LED is constantly blinking when I select an output channel (GREEN):

This problem may happen when the signal present at the

ODI input is not synchronous with the DUA II clock, or has

too much jitter.

In this situation, all outputs are muted.

The most common occurrence for this situation to happen is whenever the DUA II and the equipment to which it is

connected are both set to slave to each other. This is a pretty common user setup problem. Care should be taken in

any digital audio studio to always set one (and only one) unit as the master while programming all other units to slave

to this “master” clock.

Why does the sync LED light in RED when locking to incoming AES signals?

When set to AES sync mode with the

AES LED light on RED, it indicates that no valid AES/EBU signal has been

detected. It may be that there is no signal at all, or that this signal is not at the same sample rate than the DUA II.

Once a valid AES/EBU signal has been detected, the

AES LED light on GREEN.

The

LOCK LED should light on GREEN, to indicate that the DUA II is locked to the incoming signal.

If the

LOCK LED still light on RED, this may be that the incoming signal sample rate is out of the DUA II crystal’s

range, or that this signal has too much jitter.

What would be a typical use of the AES/EBU reference input on the back of DUA II ?

Some studios are using an AES/EBU reference signal as a house-sync, instead of a Word-Clock or a video reference.