Hi Folks,

After lots of searching and reading on these forums I decided I needed to post a question as I am unable to resolve our issues.

I am having trouble getting our MADIFace USB units to work correctly when using them in an Aggregated pair with MacOS and some Digico SD7 Consoles.

Most of our projects require around 128 channels of recording / virtual soundcheck, and the console provides 4 MADI Coaxial I/O. I have two MADIFace USB devices that have been working perfectly for the years I have had them, but these were always used as individual 64CH recorders, one for main and one for backup. When I set these two devices up in an aggregate audio device, and then try and record, we are getting what sounds like unclocked audio coming back form the devices.

We are recording in Reaper, and the audio files don't contain this clocking hash, so its a playback issue. Both units are showing valid clock via the MADI Coax connection, both Hammerfall settings are set as usual.

Changing the "Drift" setting in the Audio Midi Settings.app results in the audio becoming clocked and clean again, but only for a minute or so. I would have thought that as both MADIFace USB devices are receiving synchronous streams from the same Audio output of the console that Drift correction would not be required, but then OS X can be contradictory at times. We are getting to the point where the poor MADIFace's are becoming a liability and may need to be replaced with another unit, as we have tried everything we can to resolve this.

So... My question is to Mattias, and any others who have had experience with this scenario. What is the correct method of setting this up? And is it a reasonable expectation to consistently have 128CH via these two units?

Many thanks for your thoughts and assistance.

Tony