From 2cd48516019aee55dc4f5f53fdf5bc882c25f67f Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Sat, 22 Sep 2018 16:51:45 -0700
Subject: [PATCH] Improve PortAudio channel autodetection algorithm to
 workaround PulseAudio issues

---
 app/streaming/audio/renderers/portaudiorenderer.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/app/streaming/audio/renderers/portaudiorenderer.cpp b/app/streaming/audio/renderers/portaudiorenderer.cpp
index f6732d67..70bb8e79 100644
--- a/app/streaming/audio/renderers/portaudiorenderer.cpp
+++ b/app/streaming/audio/renderers/portaudiorenderer.cpp
@@ -151,7 +151,12 @@ int PortAudioRenderer::detectAudioConfiguration()
         return false;
     }
 
-    if (deviceInfo->maxOutputChannels > 2) {
+    // PulseAudio reports max output channels that don't
+    // correspond to any output devices (32 channels), so
+    // only use 5.1 surround sound if the output channel count
+    // is reasonable. Additionally, PortAudio doesn't do remixing
+    // for quadraphonic, so only use 5.1 if we have 6 or more channels.
+    if (deviceInfo->maxOutputChannels == 6 || deviceInfo->maxOutputChannels == 8) {
         return AUDIO_CONFIGURATION_51_SURROUND;
     }
     else {