From 9da83efbc8f180bab3a3d6a5f1c9a3c3eace2939 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Llu=C3=ADs=20Vinent?= <lluisvinentdev@gmail.com>
Date: Wed, 10 Dec 2025 23:27:37 +0100
Subject: [PATCH] Make audio source sample rate and channels configurable

Fix audio capture failures on Meta Quest devices caused by sample_rate
and num_channels mismatch with hardcoded defaults.

Changes:
- RtcAudioSource: Add optional uint? sampleRate parameter with platform-specific fallbacks
- MicrophoneSource: Accept configurable channels and sampleRate at runtime
- Allows device-specific audio configuration to match actual capabilities

Fixes: InvalidState error - sample_rate and num_channels don't match
---
 Runtime/Scripts/MicrophoneSource.cs | 12 ++++++++----
 Runtime/Scripts/RtcAudioSource.cs   |  9 ++++++---
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/Runtime/Scripts/MicrophoneSource.cs b/Runtime/Scripts/MicrophoneSource.cs
index 923df981..da680681 100644
--- a/Runtime/Scripts/MicrophoneSource.cs
+++ b/Runtime/Scripts/MicrophoneSource.cs
@@ -14,6 +14,7 @@ sealed public class MicrophoneSource : RtcAudioSource
     {
         private readonly GameObject _sourceObject;
         private readonly string _deviceName;
+        private readonly uint _sampleRate;
 
         public override event Action<float[], int, int> AudioRead;
 
@@ -27,10 +28,14 @@ sealed public class MicrophoneSource : RtcAudioSource
         /// get the list of available devices.</param>
         /// <param name="sourceObject">The GameObject to attach the AudioSource to. The object must be kept in the scene
         /// for the duration of the source's lifetime.</param>
-        public MicrophoneSource(string deviceName, GameObject sourceObject) : base(2, RtcAudioSourceType.AudioSourceMicrophone)
+        /// <param name="channels">Number of audio channels (default: 2 for stereo). Configurable at runtime.</param>
+        /// <param name="sampleRate">Sample rate in Hz (default: 48000). Configurable at runtime.</param>
+        public MicrophoneSource(string deviceName, GameObject sourceObject, int channels = 2, uint sampleRate = 48000) 
+            : base(channels, RtcAudioSourceType.AudioSourceMicrophone, sampleRate)
         {
             _deviceName = deviceName;
             _sourceObject = sourceObject;
+            _sampleRate = sampleRate;
         }
 
         /// <summary>
@@ -48,7 +53,6 @@ public override void Start()
             base.Start();
             if (_started) return;
 
-
             if (!Application.HasUserAuthorization(mode: UserAuthorization.Microphone))
                 throw new InvalidOperationException("Microphone access not authorized");
 
@@ -60,11 +64,11 @@ public override void Start()
 
         private IEnumerator StartMicrophone()
         {
-             var clip = Microphone.Start(
+            var clip = Microphone.Start(
                 _deviceName,
                 loop: true,
                 lengthSec: 1,
-                frequency: (int)DefaultMicrophoneSampleRate
+                frequency: (int)_sampleRate  // Uses configurable sample rate instead of hardcoded default
             );
             if (clip == null)
                 throw new InvalidOperationException("Microphone start failed");
diff --git a/Runtime/Scripts/RtcAudioSource.cs b/Runtime/Scripts/RtcAudioSource.cs
index ef512733..f2bc9bf8 100644
--- a/Runtime/Scripts/RtcAudioSource.cs
+++ b/Runtime/Scripts/RtcAudioSource.cs
@@ -60,16 +60,19 @@ public abstract class RtcAudioSource : IRtcSource, IDisposable
         private bool _started = false;
         private bool _disposed = false;
 
-        protected RtcAudioSource(int channels = 2, RtcAudioSourceType audioSourceType = RtcAudioSourceType.AudioSourceCustom)
+        protected RtcAudioSource(int channels = 2, RtcAudioSourceType audioSourceType = RtcAudioSourceType.AudioSourceCustom, uint? sampleRate = null)
         {
             _sourceType = audioSourceType;
 
+            // Use provided sample rate, or fall back to defaults
+            uint actualSampleRate = sampleRate ?? 
+                (_sourceType == RtcAudioSourceType.AudioSourceMicrophone ? DefaultMicrophoneSampleRate : DefaultSampleRate);
+
             using var request = FFIBridge.Instance.NewRequest<NewAudioSourceRequest>();
             var newAudioSource = request.request;
             newAudioSource.Type = AudioSourceType.AudioSourceNative;
             newAudioSource.NumChannels = (uint)channels;
-            newAudioSource.SampleRate = _sourceType == RtcAudioSourceType.AudioSourceMicrophone ?
-                DefaultMicrophoneSampleRate : DefaultSampleRate;
+            newAudioSource.SampleRate = actualSampleRate;
 
             UnityEngine.Debug.Log($"NewAudioSource: {newAudioSource.NumChannels} {newAudioSource.SampleRate}");