IShowU Audio Capture setup

I have been searching the forum but don’t see anything on this specific issue.

I am considering installing IShowU Audio Capture, prior to upgrading from High Sierra to Mojave, but I am confused about multi-output devices. The instructions for IShowU on the Audacity wiki say:

“If you need to hear what you are recording (which will usually be the case), you need to set up a “Multi-Output Device” in “Audio MIDI Setup”.”

However, a couple years ago when I was first setting up Audacity and fumbling with Soundflower, Gale made the following comment:

“Follow the instructions at … n_mac.html. Don’t create any multi-output devices. Audacity does not record from MIDI devices.”

The last two sentences have me puzzled. I do have a multi-output device set up now, probably dating from this time, but I don’t think it is being used. My use of Audacity is limited to recording – and editing – internet streaming. It is working fine, but I want to be up-to-date and ready for 64 bit. So after installing IShowU, where do I go from there? Modify my present multi-output device, substituting IShowU for Soundflower, and then select that as output in my Audacity preferences?

You should follow the instructions on the wiki. They work. You set the multi-output device as the default output device for your computer, not as the input device in Audacity. In Audacity, set iShowU Audio Capture as the input device.

Be sure to turn “Software Playthrough” off in Audacity, or you may get feedback.

Alternatively, you can set iShowU as the default output device for your computer, and as your input device in Audacity, then set Software Playthrough on. In that case you will be able to hear your source only when Audacity is recording or in monitoring mode. Setting up the multi-output device in Audio MIDI Setup is a convenience so you can hear what’s playing on your computer without having to switch between iShowU and your normal output device.

I don’t know if iShowU is 64-bit, and it shouldn’t matter one way or another as far as Audacity is concerned.

– Bill

Thanks. I’ll give it a shot. Should I uninstall Soundflower?

The business about 64 bit came up when I was fishing around for comments on Mac Mojave. Someone said they were having problems starting up Audacity because Mojave was complaining about an incompatible app, and that turned out to be Soundflower at 32 bit. That’s where I saw the recommendation to move to IShowU. Perhaps I just inferred that it was 64 bit.

I neglected to state previously that I am using Audacity 2.3.0.

Audacity 2.3.0 is still 32-bit and works fine on Mojave.

We are still hoping to get a fully functional 64-bit build of Audacity for Mac for the upcoming 2.3.1 version later this month.


I’ve got IShowU installed and working in Audacity. However, I have to use the setup with IShowU Audio Capture as the Mac default output rather than using the multi-output device including IShowU. The latter device works because I can use it to listen, but it just seems that Audacity (2.3.0) doesn’t pick up IShowU Audio Capture as an input stream from it. I’ve gone through various repetitions of the two setups, with and without Audacity and Mac restarts and machine reboots. The attached “collage” composite screen shot shows, I think, all the relevant parameters of my working setup. The wave form is a still shot of a recording, not of a listening session. Sort of “pudding proof”. (You’ll have to zoom way in to read the details.)

IShowU Audio Capture apparently provides higher level input than Soundflower. I’m used to automatically normalizing all my recordings to bring the volume up, but I don’t really have to do that now. In fact, I actually have to reduce the volume in System Preferences when auditing because it tends to be too loud. The volume slider in the upper tool bar doesn’t function.

I had hoped that Soundflower might be the source of my dropout problems (from online streaming sources) but IShowYou hasn’t brought any improvements. These probably originate upstream, as Steve suggested to me a while back. I don’t think my internet speed is a contributor because the dropouts exhibit certain constancies, whereas I know internet speed itself varies over time. Specifically, the dropouts are always around .36 seconds in length. And they often occur seemingly in pairs, which are always between 13 and 14 seconds apart. I’m hoping these data points might be of some significance to any engineer types reading this.
Screen Shot 2019-01-15 at 9.25.40 PM.jpg

So you can record steaming audio, but get dropouts?

Have you tried the suggestions here?

– Bill

I’ve worked with the buffer length, but this may be worth another try since installing IShowU. And I have been minimizing activity on the Mac while recording. But I was not aware of App Nap and have now turned it off.

To be clear – because the manual page at your link refers to “clicky” recordings – I am not getting any noises, just breaks in the sound. But that description is probably why I hadn’t looked more closely at that section of the manual.

Thanks for the tip.

For those still struggling to record sound on a Mac(Mojave), navigate to System Preferences>Security and Privacy and click the Privacy tab. Make sure that Audacity has permission to access the Microphone- the OS treats iShowU as a microphone input device.

Audacity 2.3.3, OS 10.15.2

Poster Rhubarb Custard recs to give Audacity permission to access the microphone since “the OS treats iShowU as a microphone input device.”.

That has to be done in SysPrefs > Security&Privacy > Privacy. Currently it only shows QT Player.

How do I get Audacity to show up there so I can enter a check mark for access?


I can’t get this to work. I thought it was an issue with the driver, uninstalled, installed again… but then I tried to record in QuickTime and it works. So I can’t figure out why recording won’t work in Audacity.

Input and output are on iShowU, I have tried various different set ups, using multi-output, not using it, passthru on or off under transport menu, It just won’t record. I am missing a setting or something just not sure what.

MacOS 10.16.7
2012 Mac mini - 2.5ghz dual core i5

I am stumped.