diff --git a/src/main.rs b/src/main.rs
index bfb4504..6db8415 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -46,7 +46,10 @@ fn main() {
          new_listener().listen(move |data: Vec<f32>| {
             data.iter().for_each(|x| buffer.push(*x));
             if Instant::now() - last > stream_step {
-               w.transcribe(&buffer);
+               match w.transcribe_async(&buffer) {
+                  Ok(_) => (),
+                  Err(msg) => eprintln!("{}", msg),
+               };
 
                for i in stream_retain..buffer.len() {
                   buffer[i - stream_retain] = buffer[i]
@@ -82,13 +85,19 @@ fn new_whisper(model_path: String, threads: i32, handler: Handler) -> Result<Whi
 
 impl Whisper {
    fn transcribe(&self, data: &Vec<f32>) {
-      self.transcribe_async(data).unwrap();
-      // TODO block
+      let (send, recv) = std::sync::mpsc::sync_channel(1);
+      self._transcribe_async(data, Some(send)).unwrap();
+      recv.recv().unwrap();
    }
 
    fn transcribe_async(&self, data: &Vec<f32>) -> Result<(), String> {
+      self._transcribe_async(data, None)
+   }
+
+   fn _transcribe_async(&self, data: &Vec<f32>, ack: Option<std::sync::mpsc::SyncSender<bool>>) -> Result<(), String> {
       match self.jobs.try_send(AWhisper{
          data: data.clone().to_vec(),
+         ack: ack,
       }) {
          Ok(_) => Ok(()),
          Err(msg) => Err(format!("failed to enqueue transcription: {}", msg)),
@@ -109,8 +118,20 @@ impl WhisperEngine {
          match recv.recv() {
             Ok(job) => {
                match self.transcribe(&job.data) {
-                  Ok(result) => self.handler.on_success(result),
-                  Err(msg) => self.handler.on_error(format!("failed to transcribe: {}", msg)),
+                  Ok(result) => {
+                     self.handler.on_success(result);
+                     match job.ack {
+                        Some(ack) => { let _ = ack.send(true); },
+                        None => (),
+                     };
+                  },
+                  Err(msg) => {
+                     self.handler.on_error(format!("failed to transcribe: {}", msg));
+                     match job.ack {
+                        Some(ack) => { let _ = ack.send(false); },
+                        None => (),
+                     };
+                  },
                };
             },
             Err(_) => return,
@@ -146,6 +167,7 @@ impl WhisperEngine {
 
 struct AWhisper {
    data: Vec<f32>,
+   ack: Option<std::sync::mpsc::SyncSender<bool>>,
 }
 
 struct Handler {}