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Mac OS Catalina Sound Device & Digimodes

George KF2T
George KF2T Member ✭✭✭
edited March 2020 in New Ideas
For those digital-loving Flexers using SSDR firmware 2.5 or 3.0, who prefer to operate using a Mac, and especially those who live on the edge a little with the MacOS 10.15 Catalina beta, you may have noticed that Mario Ilgen's excellent xDAX doesn't work anymore. Nor does Loopback or Sound Siphon.

Fear not - there's no need to drag out a USB sound card. Or worse, use Windows.


Source-Nexus is a FREE no-configuration needed virtual audio device that will take the place of a single xDAX channel. Follow Don Agro's excellent instructions at:


Replace Source-Nexus for Loopback. 

I've been playing with it here on my Mac mini running Catalina (beta). No issues to report - all working smoothly. I may bust open the wallet and pay an additional $25 for Source-Nexus Control, which seems to allow up to 100 virtual devices. Will report back if I do.


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Open for Comments · Last Updated


  • Ernest - W4EG
    Ernest - W4EG Member ✭✭
    edited October 2019
    Thanks Geo,
    I am looking forward to the follow up on Nexus; although, I had a small problem "of course DAX/CAT" a couple of weeks ago. I decided to tackle the situation  and I was very impressed after doing some research on the Flex website.
    I found various articles that Tim had posted and some how missed them I.E FlexVSP was written several months back. After following Tim no so wordy and to the point article, was EXCELLNT; Curing the problems I was having.
    I have not updated to v3.x.x yet although I heard that some of the current issues with DAX/CAT maybe resolved soon. 
    Have not heard/seeing you on the screen for awhile. I am still operating FT-8
    Best regards
  • Scott Oakland
    Scott Oakland Member
    edited March 2020
    Hi Geo, I emailed you. I tried Source-Nexus (I am using Mojave). Cannot understand how to use this driver and get the audio from DogParkSDR to WSJT-X. Been at it for hours trying various sound apps, no joy. Just cannot get audio even to appear in DogPark SDR never mind WSJT-X. Can someone help?
  • Ted  VE3TRQ
    Ted VE3TRQ Member ✭✭✭
    edited August 2019
    The key to using dogparkSDR to pass audio to/from an app is the following (from the dogparkSDR on-line manual):

    "dogparkSDR - enable Mac Audio and turn off TX DAX in the dogparkSDR Radio prefs, select None for DAX in the Slice prefs..."

    After that, it is as simple as selecting the sound driver in the dogparkSDR and wsjt-x audio prefs. With LoopBack, I had it running in under a minute. No clue about Source-Nexus Free - couldn't get the installer to put anything in under High Sierra (which I am still stubbornly running :-) 
  • Ted  VE3TRQ
    Ted VE3TRQ Member ✭✭✭
    edited August 2019
    OK, some more testing. iShowU Audio Capture was installed, BUT needed to be allowed in Security & Privacy. Even worse, the mouse would not work on the "Allow...". I had to turn on Accessibility / Mouse & Trackpad / Enable Mouse Keys before I could see the kext drivers blocked! Then I saw both iShowU and Source-Nexus. After allowing kext load, the sound devices show up (and, of course, are available to be chosen in wsjt-x and dogparkSDR).
  • George KF2T
    George KF2T Member ✭✭✭
    edited December 2019
    Here’s a quick rundown of how to use your Mac, Flex, and WSJT-X with 2.51+ and/or OS 10.15.


  • Maurice PC9T
    Maurice PC9T Member
    edited August 2019
    I have WSJT-X working with iShowU, but the only thing I miss is hearing sound.

    With source nexus there was also no sound but also no receiving in WSJT-X.

    But when I go to use USB must I switch in DogPark by output to system?

    Or is there still something missing?

  • Ted  VE3TRQ
    Ted VE3TRQ Member ✭✭✭
    edited August 2019
    Sorry, can’t really help - I use Loopback. You get what you pay for :-(
  • Don Agro
    Don Agro Member
    edited September 2019
    The latest update to LoopBack supports Catalina.
  • John WA7UAR
    John WA7UAR Member ✭✭✭
    edited February 2020
    Here is recent information from RogueAmoeba.com (developers of LoopBack and other Mac-focused audio products) that I wanted to crosspost here for general reference.

    A Note on Catalina and Audio Unit plugins

    If you use third-party Audio Units on your Mac (in Audio Hijack or SoundSource, for instance), you should be aware of changes made by Apple In Catalina. These changes mean that at present, many third-party plugins aren't compatible with Catalina.

    Audio Unit plugins on Catalina are required to be both “code signed” and “notarized”. Plug-in developers will be the ones to worry about that. However, end users should be aware that very few third-party Audio Units currently meet these requirements.

    If you depend on Audio Units in your work, be extremely cautious about updating to 10.15. Check with the developers of your Audio Units for updates, which will be necessary. Further, for the most critical production setups, setting up a test machine is a great way to verify that everything works as expected before updating your main machine.
  • Gregory Stobbs
    edited January 2020
    In KF2T's helpful write-up on how to configure DogparkSDR for FT8, he indicates that the Tx level should be set using the Mic slider in the DogparkSDR Audio preference. Can anyone suggest which DogparkSDR meter I would use to determine the proper Tx audio level, and roughly what dB reading I should be looking to achieve? I'm thinking it would be the MIC or MIC PEAK meter(s). I just want to make sure I'm not overdriving the Tx audio. N8GAS

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