+ timeval now;
+ gettimeofday(&now, nullptr);
+
+ // The meters are somewhat inefficient to update. Only update them
+ // every 100 ms or so (we get updates every 5–20 ms).
+ double last_update_age = now.tv_sec - last_audio_level_callback.tv_sec +
+ 1e-6 * (now.tv_usec - last_audio_level_callback.tv_usec);
+ if (last_update_age < 0.100) {
+ return;
+ }
+ last_audio_level_callback = now;
+