ios_voice_unit.rs:1033: change the condition from `mix_stats.peak_i16 == 0` to `mix_stats.peak_i16 == 0 && !muted`. When the user mutes the channel via output_muted, the downmix helper fills the output buffer with silence (peak = 0), which previously falsely incremented the output_underrun counter. The mute toggle is intentional silence, not a real underrun.
Note: this does not address the separate false positive where peak_i16 == 0 with output unmuted but no audio incoming (e.g., just joined a channel with no remote speaking). A complete fix would require tracking whether the audio handler actually produced data; deferred to a follow-up.
Edison Jwa
957d68f39d