Noise on input

I tried to do a 16 track capture yesterday with my 2 Mytek 8x192 interfaces via Firewire at 24bit/48k.
Inputs 1-8 saw and captured audio, but when I armed 9-16, all I got was noise.

The control panel software for the converters says everything is perfect on their side of things, and CoreAudio sees all 16 ins as well.

Now I’m questioning Jack and Ardour itself. Can anyone offer any insight/experience/assistance?

My 1TB drive on its own FW buss (cardbus - I’m on a 17" 1.67 G4 PowerBook with 2GB of RAM running OSX.5.4), with the converters on the on-board FW buss. The drive performed admirably, and the 2nd Mytek passed audio…if I can get this sorted, I’ll bet on capturing 24 tracks at this bit depth/FS without overloading the processor, as well as get into a pay-per-capture scenario with Ardour. If ProTools LE can do 32 tracks on this machine, I’m sure Ardour is up to the task as well. I’m guessing this is just a config error or I need to run a different version of jack, or learn more about it’s config.

Hmm this sounds odd. How many ins and outs is Jack seeing? Do these show up as a single device in System Preferences>Audio or do they show up as two different devices?

If the inputs and outputs are availiable on your system as a single device, then Ardour and Jack should have no problem with it to my knowledge. If they show up as two seperate devices in your Audio System Preferences dialog, you will likely need to set up an aggregate device for Jack for them, and should time code lock them in this sort of situation.


One device. It’s scalable. Depending on F(s), I can chain as many as 8 of these together.

When I open Audio MIDI Setup, I get a pulldown to select between 2 8ch streams on both the input and output side.
They show up in JACK as capture1-16, but when I arm tracks 9-16, all I get is noise.

Let’s take this back a step and assume Jack is fine. Audio MIDI setup should be set with Mytek as Input and JackRouter as output, correct? Ardour sees Jack as its input if I understand this like I hope I do.

Ardour automatically uses Jack. It doesn’t have any other choice. So whatever Jack is set up to use is what you will be using. Audio MIDI setup doens’t matter in this case.

That being said, can you grab a screenshot of the dropdown in AudioMIDI setup you were referring to and put it up and post a link here for me to look at? Not sure what you are referring to there.

Also what happens if you route input 1 to track 9 in Jack? What about Input 9 to track 1? Thanks.



this was a Firmware bug that I’m working with the manufacturer to rectify.

Thanks for the update, while I am happy it wasn’t Jack, it still sucks to not be able to use all your inputs.