only enable microphone when in a voice channel

src/abaddon.cpp

@@ -427,6 +427,8 @@ void Abaddon::DiscordOnThreadUpdate(const ThreadUpdateData &data) {
 
 #ifdef WITH_VOICE
 void Abaddon::OnVoiceConnected() {
+    m_audio->StartCaptureDevice();
+
     auto *wnd = new VoiceWindow(m_discord.GetVoiceChannelID());
     m_voice_window = wnd;
 
@@ -473,6 +475,7 @@ void Abaddon::OnVoiceConnected() {
 }
 
 void Abaddon::OnVoiceDisconnected() {
+    m_audio->StopCaptureDevice();
     m_audio->RemoveAllSSRCs();
     if (m_voice_window != nullptr) {
         m_voice_window->close();