2 files changed, 13 insertions, 3 deletions
diff --git a/modules/minimp3/audio_stream_mp3.cpp b/modules/minimp3/audio_stream_mp3.cpp
index 2cc974322d..7b52ef178a 100644
--- a/modules/minimp3/audio_stream_mp3.cpp
+++ b/modules/minimp3/audio_stream_mp3.cpp
@@ -37,11 +37,13 @@
 
 #include "core/io/file_access.h"
 
-void AudioStreamPlaybackMP3::_mix_internal(AudioFrame *p_buffer, int p_frames) {
-	ERR_FAIL_COND(!active);
+int AudioStreamPlaybackMP3::_mix_internal(AudioFrame *p_buffer, int p_frames) {
+	ERR_FAIL_COND_V(!active, 0);
 
 	int todo = p_frames;
 
+	int frames_mixed_this_step = p_frames;
+
 	while (todo && active) {
 		mp3dec_frame_info_t frame_info;
 		mp3d_sample_t *buf_frame = nullptr;
@@ -60,6 +62,7 @@ void AudioStreamPlaybackMP3::_mix_internal(AudioFrame *p_buffer, int p_frames) {
 				seek(mp3_stream->loop_offset);
 				loops++;
 			} else {
+				frames_mixed_this_step = p_frames - todo;
 				//fill remainder with silence
 				for (int i = p_frames - todo; i < p_frames; i++) {
 					p_buffer[i] = AudioFrame(0, 0);
@@ -69,6 +72,7 @@ void AudioStreamPlaybackMP3::_mix_internal(AudioFrame *p_buffer, int p_frames) {
 			}
 		}
 	}
+	return frames_mixed_this_step;
 }
 
 float AudioStreamPlaybackMP3::get_stream_sampling_rate() {
@@ -210,6 +214,10 @@ float AudioStreamMP3::get_length() const {
 	return length;
 }
 
+bool AudioStreamMP3::is_monophonic() const {
+	return false;
+}
+
 void AudioStreamMP3::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_data", "data"), &AudioStreamMP3::set_data);
 	ClassDB::bind_method(D_METHOD("get_data"), &AudioStreamMP3::get_data);
diff --git a/modules/minimp3/audio_stream_mp3.h b/modules/minimp3/audio_stream_mp3.h
index ce001fc418..3c8bdd8c53 100644
--- a/modules/minimp3/audio_stream_mp3.h
+++ b/modules/minimp3/audio_stream_mp3.h
@@ -51,7 +51,7 @@ class AudioStreamPlaybackMP3 : public AudioStreamPlaybackResampled {
 	Ref<AudioStreamMP3> mp3_stream;
 
 protected:
-	virtual void _mix_internal(AudioFrame *p_buffer, int p_frames) override;
+	virtual int _mix_internal(AudioFrame *p_buffer, int p_frames) override;
 	virtual float get_stream_sampling_rate() override;
 
 public:
@@ -103,6 +103,8 @@ public:
 
 	virtual float get_length() const override;
 
+	virtual bool is_monophonic() const override;
+
 	AudioStreamMP3();
 	virtual ~AudioStreamMP3();
 };