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Sound Byte FAQ

Note: If some sound files will not play: Sound files that are not actually stored on your device (they are in iCloud), are in Apple Music, or are DRM protected generally cannot be played by Sound Byte. That is because Apple will not allow 3rd party apps to fully access these files. I agree this is frustrating, and wish Apple did not have this policy. You can always move sound files directly to Sound Byte via iTunes File sharing, so they will play without problems, as described below.

Also, we've found that iOS often has issues playing variable bitrate sound files. Change to a fixed bitrate, that should solve the problem.

Getting started

When you first run Sound Byte, you see an array of empty carts. You can assign a sound file to a cart by following these steps:

First, touch a cart and hold your finger down for about one second, then release. This will bring up the Cart Options.

Now you have two choices. If you have sound files in you music library on your device (running iOS 6 or later) that you wish to play, tap "Music Library". You will see a list of these sound files. You can select one of them. Please note that the sound files must actually be on your device, not in iCloud, this is an Apple restriction. If your sound files are not appearing or playing, you will need to find a way to move them to your local music library, or use iTunes File sharing as described below.

If you wish to assign a sound file that you have transferred to your device using File Sharing via the iTunes app on your computer (instructions for doing this are at the bottom of this page), then tap Sound file. You will be presented with a list of all of the sound files installed for Sound Byte, tap on the desired file.

Configuring carts

Sound Byte has 75 carts, arranged on a 5 by 15 rack. To define the sound file for a cart, or set Cart Options, touch the cart and hold your finger down for about one second, then release.

To select the sound file, touch on Sound File or Music Library. You will be presented with a list of all of the available sound files, touch on the desired file.

Tap on Color Color to set the background color for the cart.

The cut in time, in seconds, specifies where the sound file starts to play. Setting it to 5, for example, will start playback 5 seconds into the file.

The fade time, in seconds, can be specified, this will be used when a cart is faded in or out.

You can also edit the cart title (it defaults to the name of the sound file), as well as the Looping Count (number of times sound playback will loop, the default, zero means just play once, setting it to 2 for example would cause it to play a total of three times).

Five switches are also used to control the cart operation:

  • Touch aborts other carts - touching this cart will stop playback of all other carts
  • Touch fades other carts - touching this cart fade out all other carts
  • Touch restarts playback - touching this cart will start playback at the beginning
  • Fade in playback - the cart will be faded in when it starts
  • Fade out playback - the cart will be faded out when it stops
When changing sliders in settings, try tapping them vs using a swipe, as sometimes the change is not otherwise saved.

The cart volume can be changed with the slider.

Tapping on clear cart will clear out the cart information. This can be used to “erase” a cart and not have it display in the rack.

Playing carts

Tap on a cart to start playback. Tap on it again to stop. Tap on the Stop button to stop all playing carts.

When a cart is playing, the title will be faded slightly, and the elapsed and remaining times will be displayed.

You can fade out a playing cart by swiping to the left. Or you can tap the Fade button, which will fade out all playing carts.

Swiping to the right on a cart will pause playback of that cart. Tapping on the Pause button will pause playback of all playing carts.

Moving carts

To swap two carts, touch with two fingers on one of the carts for a second or so and then release. The title of that cart will change, telling you to tap on the other cart. The two carts will be swapped. To cancel a swap, tap on the cart with the message, the first cart you tapped.

General Controls

The left and right arrows can be used to cycle through the five racks of carts, each rack has 75 carts.

Tapping Setup allows the title of the rack to be set.

The Pause, Fade, and Stop buttons allow a playing cart to be paused, faded out, or stopped, respectively.


Tapping Setup allows the title of the rack to be set, as well as enabling several features:

Rack name - sets the title of the rack

Mark played carts - when a cart is played, the text PLAYED will be displayed over the cart, to let you know that you have already played it.

Disable played carts - carts that have been played will be disabled, so they cannot be played again.

Clear marked carts - carts that have been marked or disabled will be unmarked, and allowed to be played again.

Frame playing carts - a white border is drawn around the cart, to make it more obvious.

Show playback progress - a green progress indicator is drawn visually showing how much playback has elapsed and how much is remaining.

Log played carts - a text file called play_log.txt showing which carts have been played is written to the documents folder, which you access via iTunes, in the same way to add sound files. This text file has one entry per line, with the date and time of playback, the button title, and the sound file name.

Number of carts - You can select how many carts are displayed in the X/Y rack grid. Displaying fewer carts makes the size of each cart larger, which may be useful in some applications, as they are easier to see.

Steps to use iTunes File Sharing

Note that with macOS 10.15 Catalina, you can use Finder to transfer the sound files, as the iTunes app no longer exists. See this page from Apple for details on how to do this:

Please note that the user interface and layout of iTunes changes between versions, so the steps and screenshots described below may not match exact what you see, but should be close enough for you to understand what to do. If you need more precise steps for your particular setup, I would suggest that you find out what version of iTunes you have, and do a web search for instructions on using File Sharing with that particular version):

Connect your device to your computer via a USB cable, and launch iTunes on your computer, if it has not automatically started.

Next, click on the little device icon in the upper left area of the main iTunes window, there is a small screenshot showing it circled in red below:

Now your device name should appear. Next you want to click on Apps, which I have circled in red below:

Now, scroll down to the very bottom of the iTunes window until you see File Sharing. It may not be visible on your screen unless you scroll all the way down.

Click on the Sound Byte App on the left.

Click on the Add button on the lower right to select a sound file to add. Repeat this for all the sound files you want to add.

If you want to delete a sound file, you can select it from the list, then hit the DELETE key on your keyboard.

You may need to sync your device when finished.

Solutions to Problems

Some users have reported no sound on the built in speaker. One solution they have used is:
Go to Settings, select General,
At the top, there is Ringer and Alerts. In that section, set Volume all the way up.

If you noticed the sound dropping out after a second or so, go to your device Settings, and then Music, and make turn off Sound Check. Also make sure you do not have any other apps running that could affect sound playback.

Back to Sound Byte

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Last modified June 29, 2017