Under The Microscope

Rogue Amoeba’s New Ultimate Podcast Bundle

Since way back in the mid-2000s, we’ve been delighted to help folks create their own podcasts. It’s been over a decade since Audio Hijack first added the ability to record both halves of a Skype conversation. In that time, podcasting has flourished, and our product lineup has grown to include audio tools to handle nearly all aspects of a podcasting workflow.

To record, Audio Hijack will get you set, whether you just need to capture from local microphones, or you want to record both halves of a Skype or other VoIP conversation.

Using Loopback, it’s possible to route audio between applications, so all parties on a VoIP call can hear the sounds you want to play.

Our newest app Farrago provides rapid-fire soundboards so you can drop in sound effects and musical accompaniment as you record.

Finally, with Fission, you can quickly and losslessly edit your audio recordings and add podcast chapters.

We’re now offering all four of these tools in one money-saving purchase. With the Ultimate Podcast Bundle, you’ll get license keys to unlock all four of these apps at a substantial savings.

If you’re interested in getting into podcasting, this new bundle is a great place to begin. You’ll save over $50 on four powerful tools to get your new show rolling. Check out the Ultimate Podcast Bundle page for more details.

Farrago Fools

I imagine that most geek parents have used the old “talking computer” trick on their kids at some point.

You can’t argue with machine learning.

I’ve used it enough that whenever my children hear any robotic voice coming from a device, they completely ignore the voice and search the house for me instead.1

Rather than resorting to my usual April Fool’s Day joke2, I decided to up the ante a bit this year. Inspired by one mischievous user, I decided to prank my kids with Rogue Amoeba’s newest app Farrago. Ultimately, I wound up using three of our apps for this prank, a record the marketing department wants me to tell you to try and break.

The Setup

To start, I downloaded a clip from Studio Ghibli’s “The Secret World of Arrietty”. This movie is about a family of tiny people who secretly live in a house of ordinary humans, sneaking around the house and scavenging from them while they sleep.

I then used our audio editor Fission to divide the clip up into segments containing various sound effects (such as footsteps, climbing noises, etc.), as well as dialogue parts. I saved those out, so I had over a dozen different sounds.

Isolating clips in Fission.

Once I had my individual files, I loaded them into Farrago for playback. Next, I configured Airfoil to capture Farrago’s audio to Airfoil Satellite running on my phone.

Do you hear footsteps?

The Delivery

I first tried this on the girls. While saying goodnight, I secretly slipped the phone under one of their beds. Then I snuck back downstairs and began playing audio in Farrago. After a few minutes of no response, I wondered if something had gone wrong. When I went back upstairs to check, I discovered they hadn’t heard anything. Apparently, the volume was low enough that it couldn’t be heard over the noise of their fan.

Undaunted, I explained the prank to them and recruited them to help me try it out on the boys. I repeated the same setup with the phone, making sure the volume was turned up, then snuck back to the girl’s room where we started playing clips.

The boys responded immediately, searching under their bed to find the source of the “footsteps” and talking. Once they found it they ran into the girls’ room, where we were all laughing a bit too loudly to be stealthy.

Next Time

If I were to do this again next year, aside from making sure the volume was turned up on the phone, I’d come up with a way to hide the phone better. Even better would be hiding multiple devices in the same room and alternating transmitting between them.

Hopefully, this prank will last longer than the talking computer trick.


  1. I’m not sure how this will affect their odds of survival in the event of a robot uprising. ↩︎

  2. Wherein I hold a dollop of ketchup in my hand and pretend to cut myself while slicing an apple at the breakfast table. This trick honestly worked for about seven years straight. ↩︎

AirPlay Volume Bug: Goto Mute

Earlier today, we shipped an update to our home audio streamer Airfoil for Mac. The just-released version 5.7.3 works around a bug introduced by Apple in tvOS 11.3. This bug is likely to affect not just Airfoil users, but anyone who sends AirPlay audio to their Apple TV, so a summary of Apple’s bug may be helpful.

In short, for Apple TV receiving audio via AirPlay, volume handling is broken on tvOS 11.3. When the sender has its volume set to zero, audio will still be heard from the Apple TV. You can try it yourself by setting the iTunes volume slider to the far left, as seen below. Send audio to an Apple TV running tvOS 11.3, and you’ll still hear audio leaking out of the AppleTV. This issue occurs with any source sending to the device, including Apple’s iTunes and iOS, as well as previous versions of our own Airfoil.

The sending volume in iTunes is at 0, but audio will still be heard.

A little background on AirPlay volume control helps explain what’s occurring. To eliminate slider latency, AirPlay audio has its volume set on the receiving end (here, that’s the Apple TV). To do this, the sender (here, iTunes) provides the volume level using a special SET_PARAMETER volume command. As a result, adjusting the volume slider in iTunes immediately changes the remote volume, with no lag.

That volume command allows a value range of 0 dB for full volume down to -30 dB for full reduction. However, a -30 dB reduction is often not enough to mute very loud audio, so there’s also a special value to force full muting. When audio should be fully muted, a sender tells the receiver to set volume to -144 dB. The receiver then knows it should not play any audio at all.

With the tvOS 11.3 update, this mute special case is now kicking in at -145 dB, instead of -144 dB. Though it’s impossible to be certain without actually seeing Apple’s source code, this is very likely to be an off-by-one bug. Specifically, it seems that a less-than-or-equal sign got changed to a less-than.

The previous code would have looked something like this:

if $volume <= -144


While the updated code would look like this:

if $volume < -144


This one small change leads to a very unexpected result for users. We expect Apple will correct this bug in a future tvOS update, but until they do, iTunes and iOS sending won’t properly mute audio to the Apple TV devices.

For our part, once we understood the problem, we could update Airfoil for Mac to work around it. Be sure update to Airfoil for Mac 5.7.3, which will correctly mute audio for all versions of tvOS (Airfoil for Windows users, watch for an update coming soon as well).

Licensing Rogue Amoeba’s Audio Capture Technology

Over the years, we’ve received numerous requests from other businesses looking to license our audio capturing technology. Until now, we always declined these offers, preferring to focus on improving both the technology and our own applications which use it.

Recently, however, we revisited the possibility of licensing. Our audio capture code has been continuously improved for over a decade, and it’s now incredibly reliable. This technology is used by tens of thousands of our users every day, in Airfoil, Audio Hijack, Loopback, and Piezo. We’re tremendously confident in what we’ve built.

Because of this, we’re now pleased to announce licensing opportunities for our audio capture technology, ACE.1 ACE makes it possible for Mac apps to capture audio from one or more individual processes, as well as all audio from the entire system at once. The same power which drives some of our biggest apps is now available to outside developers as well.

If you develop an application which could benefit from audio capture2, please see our new licensing page, then get in touch!


  1. ACE has had multiple names over the years, starting with “Instant Hijack” and then “Instant On”. This newest name is intended to better convey the many uses of our licensable framework. ↩︎

  2. Examples include apps dedicated to screen sharing, VNC/remote access, game streaming, and more. ↩︎

We Just Can’t Shake Him

Recently, a familiar face returned to Rogue Amoeba, and not for the first time. We’re glad to announce that our old friend Lee Falin is back on the team once again.

Lee has followed a rather roundabout career path over the past decade. He first joined us in late 2008 to work as a support technician, and a couple years later transitioned into the role of part-time Windows dev. He eventually took on full-time development of Airfoil for Windows for several years. However, he also spent some doing academic research and teaching as a university professor, but soon discovered that academia was not an ideal place for teaching about software development. During that time, Lee often worked part-time here, but even when he left fully, he still wound up doing contract work for us on iOS and Android.

Now, Lee’s returning to us in a full-time role. He’ll be focusing on Mac development, while likely also assisting on work on other platforms, and we’re delighted to have him back. His varied talents are a great asset, and we can’t wait to unveil the new updates he’ll help us create.

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