PreferenceSpecifiers Title Codecs Type PSGroupSpecifier DefaultValue Key speex_16k_preference Title Speex 16Khz Type PSToggleSwitchSpecifier DefaultValue Key speex_8k_preference Title Speex 8Khz Type PSToggleSwitchSpecifier DefaultValue Key opus_preference Title Opus 48kHz Type PSToggleSwitchSpecifier DefaultValue Key silk_24k_preference Title Silk 24Khz Type PSToggleSwitchSpecifier DefaultValue Key silk_16k_preference Title Silk 16Khz Type PSToggleSwitchSpecifier DefaultValue Key aaceld_22k_preference Title AAC-ELD 22kHz Type PSToggleSwitchSpecifier New item DefaultValue Key aaceld_44k_preference Title AAC-ELD 44kHz Type PSToggleSwitchSpecifier DefaultValue Key amr_preference Title AMR Type PSToggleSwitchSpecifier DefaultValue Key g722_preference Title G722 Type PSToggleSwitchSpecifier DefaultValue Key g729_preference Title G729 Type PSToggleSwitchSpecifier DefaultValue Key gsm_preference Title GSM Type PSToggleSwitchSpecifier DefaultValue Key ilbc_preference Title ILBC Type PSToggleSwitchSpecifier DefaultValue Key pcmu_preference Title PCMU Type PSToggleSwitchSpecifier DefaultValue Key pcma_preference Title PCMA Type PSToggleSwitchSpecifier Key audio_advanced_group Title Advanced Type PSGroupSpecifier Key playback_gain_preference Title Playback gain Type PSTextFieldSpecifier KeyboardType NumbersAndPunctuation DefaultValue 0 IASKTextAlignment IASKUITextAlignmentRight Key microphone_gain_preference Title Microphone gain Type PSTextFieldSpecifier KeyboardType NumbersAndPunctuation DefaultValue 0 IASKTextAlignment IASKUITextAlignmentRight DefaultValue Key adaptive_rate_control_preference Title Adaptive rate control Type PSToggleSwitchSpecifier DefaultValue 32 Key audio_codec_bitrate_limit_preference Title Codec bitrate limit Titles 10 kbits/s 15 kbits/s 20 kbits/s 32 kbits/s 64 kbits/s 128 kbits/s Type PSMultiValueSpecifier Values 10 15 20 32 64 128