ALSA: remove variable callback (refs #5273)

modules/audio_output/alsa.c

@@ -147,9 +147,8 @@ static void DumpDeviceStatus (vlc_object_t *obj, snd_pcm_t *pcm)
 static void Probe (vlc_object_t *obj)
 {
     /* Due to design bug in audio output core, this hack is required: */
-    if (var_Type (obj, "audio-device"))
-        return;
-
+    if (var_Type (obj, "audio-device") == 0)
+    {
         /* The variable does not exist - first call. */
         vlc_value_t text;
 
@@ -158,7 +157,7 @@ static void Probe (vlc_object_t *obj)
         var_Change (obj, "audio-device", VLC_VAR_SETTEXT, &text, NULL);
 
         GetDevices (obj, NULL);
-
+    }
     var_AddCallback (obj, "audio-device", aout_ChannelsRestart, NULL);
     var_TriggerCallback (obj, "intf-change");
 }
@@ -697,6 +696,7 @@ static void Close (vlc_object_t *obj)
     aout_sys_t *sys = aout->sys;
     snd_pcm_t *pcm = aout->sys->pcm;
 
+    var_DelCallback (obj, "audio-device", aout_ChannelsRestart, NULL);
     snd_pcm_drop (pcm);
     snd_pcm_close (pcm);
     free (sys);