fix audio input device settings

res/layouts/pages/settings_audio.xml.lua

@@ -31,6 +31,14 @@ function update_checkbox_setting(id, value)
     document.input_device_select.enabled = recording_enabled
     document.input_volume_inner.enabled = recording_enabled
     document.input_volume_outer.enabled = recording_enabled
+
+    local selectbox = document.input_device_select
+    local info = audio.input.get_input_info()
+    if info then
+        selectbox.value = info.device_specifier
+    else
+        selectbox.value = app.get_setting("audio.input-device")
+    end
 end
 
 function create_checkbox(id, name, tooltip)
@@ -84,6 +92,7 @@ function on_open()
         table.insert(devices, {value=name, text=name})
     end
     selectbox.options = devices
+
     local info = audio.input.get_input_info()
     if info then
         selectbox.value = info.device_specifier

src/audio/AL/ALAudio.cpp

@@ -5,6 +5,7 @@
 
 #include "debug/Logger.hpp"
 #include "alutil.hpp"
+#include "util/stringutil.hpp"
 #include "../MemoryPCMStream.hpp"
 
 static debug::Logger logger("al-audio");
@@ -99,6 +100,8 @@ ALInputDevice::ALInputDevice(
 
     if (deviceName) {
         deviceSpecifier = std::string(deviceName);
+        logger.info() << "created input device with specifier "
+                      << util::quote(deviceSpecifier);
     } else {
         logger.warning() << "could not retrieve input device specifier";
     }

src/audio/audio.cpp

@@ -205,12 +205,17 @@ void audio::initialize(
             return;
         }
         if (enabled) {
-            logger.info() << "recording enabled; input device is "
-                          << settings.inputDevice.get();
+            const auto& targetDevice = settings.inputDevice.get();
+            logger.info() << "recording enabled; target input device is "
+                          << (targetDevice.empty() ? "not specified"
+                                                   : targetDevice);
             ::input_device = backend->openInputDevice(
                 settings.inputDevice.get(), 44100, 1, 16
             );
-            ::input_device->startCapture();
+            if (::input_device != nullptr) {
+                logger.error() << "could not create input device";
+                ::input_device->startCapture();
+            }
         } else {
             if (::input_device) {
                 ::input_device->stopCapture();

src/settings.hpp

@@ -18,7 +18,7 @@ struct AudioSettings {
     NumberSetting volumeAmbient {1.0f, 0.0f, 1.0f, setting_format::percent};
     NumberSetting volumeMusic {1.0f, 0.0f, 1.0f, setting_format::percent};
 
-    StringSetting inputDevice {"auto"};
+    StringSetting inputDevice {""};
 
     FlagSetting acousticEffects {true};
 };