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Vivox Core SDK

Vivox Core SDK

Vivox
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Vivox Core SDK
  • Overview
  • Before you begin
  • Get started
  • Release notes
  • Developer Guide
    • Client SDK basics
    • Channels
    • Presence management
    • Messaging
    • Manage audio
    • Couch co-op
    • Android app development
    • iOS app development
      • Required Info.plist settings for iOS apps
      • Acoustic echo cancellation
      • Initialize the AVAudioSession on app startup
      • AVAudioSessionModeVoiceChat
      • Disable the Vivox SDK internal AEC
      • iOS known limitations
        • Cannot set iOS device volume to 0 when Voice-Processing I/O unit is active
        • The iOS microphone recording indicator
        • AVAudioPlayer volume inconsistencies
        • Volume shifts
        • Restore audio volume
    • macOS app development
    • Windows app development
    • Real-time recording
    • Speech-to-text audio transcription
    • Text-to-speech
    • Troubleshooting
  • Reference
  • Privacy overview
  1. Vivox Core SDK documentation
  3. iOS app development

Cannot set iOS device volume to 0 when Voice-Processing I/O unit is active

Understand iOS volume constraints when the Voice-Processing input/output unit is active.
Read time 1 minute
Last updated 8 months ago
When using an iOS device and the Voice-Processing I/O unit is active, you cannot set the volume of the iOS device to 0. For more information, see the Apple developer documentation on AVAudioSessionCategoryPlayAndRecord.
A possible workaround for this functionality when you are using Vivox on iOS is to observe changes in AVAudioSession.outputVolume that are being set by the user and then mute your game audio output based on the observed value. For example implementations of this workaround, refer to How to: Observe the iOS volume level to programmatically mute game audio in the Unity Support Knowledge Base.
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