No Sound on the Odyssey Translator iPhone App
If you aren't getting any sound from an Odyssey Translator app on your iPhone, the problem is likely your iPhone's volume settings. The Apple iPhone has two volume settings: one for audio and one for video. Because the Odyssey Translator app uses the iPhone's video volume, you might not get any sound from it, even if you crank up the sound to the maximum using the iPhone's volume buttons.
1 Getting Sound
First make sure you have the latest version of the Odyssey Translator app by checking for an update in the App Store. If you're still not getting sound, launch another app on your iPhone, like the native Videos app or YouTube. Play a video and then use the volume control within the app to turn the volume up to an audible level. Go back to the Odyssey Translator app and press a translation app, while also turning up the volume button. This undocumented fix should solve the problem.