ao_coreaudio: log hotplug events explicitly

audio/out/ao_coreaudio.c

@@ -345,9 +345,12 @@ static void uninit(struct ao *ao)
 
 static OSStatus hotplug_cb(AudioObjectID id, UInt32 naddr,
                            const AudioObjectPropertyAddress addr[],
-                           void *ctx) {
-    reinit_device(ctx);
-    ao_hotplug_event(ctx);
+                           void *ctx)
+{
+    struct ao *ao = ctx;
+    MP_VERBOSE(ao, "Handling potential hotplug event...\n");
+    reinit_device(ao);
+    ao_hotplug_event(ao);
     return noErr;
 }