From f69384525acf4c77fb1f050dc47775c56d56f1b0 Mon Sep 17 00:00:00 2001
From: Hubert Chrzaniuk <hubert.chrzaniuk@mudita.com>
Date: Thu, 26 Nov 2020 09:46:30 +0100
Subject: [PATCH] [EGD-4332][EGD-4482] Fix playback of mono sound in headphones
 (#1080)

Addressed problem - when playing files containing only one
audio channel the sound could be heard in only one speaker.
---
 changelog.md                                       |  4 ++++
 module-audio/Audio/Operation/PlaybackOperation.cpp | 13 ++++++++++---
 module-audio/Audio/decoder/decoder.hpp             |  5 +++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/changelog.md b/changelog.md
index 70b14f5efb6c04d86701586359c52163fb80a664..df751e9c4695b5dfa0c674c71d4819b89c90a73b 100644
--- a/changelog.md
+++ b/changelog.md
@@ -4,6 +4,10 @@
 
 * `[cellular]` Integration with basic flow for SIM card (cellular<>GUI)
 
+### Fixed
+
+* `[audio]` Fix playback of mono sound using headphones
+
 ## [0.48.1 2020-11-23]
 
 ### Added
diff --git a/module-audio/Audio/Operation/PlaybackOperation.cpp b/module-audio/Audio/Operation/PlaybackOperation.cpp
index 2aee8aa21789114dca692720692fb748e5fe285c..0f871f3a6f262b273c61e22e0a467d0de8647c0c 100644
--- a/module-audio/Audio/Operation/PlaybackOperation.cpp
+++ b/module-audio/Audio/Operation/PlaybackOperation.cpp
@@ -90,9 +90,16 @@ namespace audio
         eventCallback = callback;
         state         = State::Active;
 
-        currentProfile->SetInOutFlags(tags->num_channel == 2
-                                          ? static_cast<uint32_t>(bsp::AudioDevice::Flags::OutputStereo)
-                                          : static_cast<uint32_t>(bsp::AudioDevice::Flags::OutputMono));
+        if (tags->num_channel == channel::stereoSound) {
+            currentProfile->SetInOutFlags(static_cast<uint32_t>(bsp::AudioDevice::Flags::OutputStereo));
+        }
+        else {
+            currentProfile->SetInOutFlags(static_cast<uint32_t>(bsp::AudioDevice::Flags::OutputMono));
+            if (currentProfile->GetOutputPath() == bsp::AudioDevice::OutputPath::Headphones) {
+                currentProfile->SetOutputPath(bsp::AudioDevice::OutputPath::HeadphonesMono);
+            }
+        }
+
         currentProfile->SetSampleRate(tags->sample_rate);
 
         auto ret = audioDevice->Start(currentProfile->GetAudioFormat());
diff --git a/module-audio/Audio/decoder/decoder.hpp b/module-audio/Audio/decoder/decoder.hpp
index 949495c38ec42ba163b506af58daf976d8c1920c..ac8107383e45535069cb344fb953ff7230d70a6e 100644
--- a/module-audio/Audio/decoder/decoder.hpp
+++ b/module-audio/Audio/decoder/decoder.hpp
@@ -12,6 +12,11 @@
 
 namespace audio
 {
+    namespace channel
+    {
+        constexpr inline auto monoSound   = 1;
+        constexpr inline auto stereoSound = 2;
+    } // namespace channel
 
     struct Tags
     {