diff --git a/software/modules/audiocore/audiocore.py b/software/modules/audiocore/audiocore.py
index eeb3354..ea7dd11 100644
--- a/software/modules/audiocore/audiocore.py
+++ b/software/modules/audiocore/audiocore.py
@@ -2,7 +2,8 @@
 # Copyright (c) 2025 Matthias Blankertz <matthias@blankertz.org>
 
 import _audiocore
-from asyncio import ThreadSafeFlag
+import asyncio
+from asyncio import Lock, ThreadSafeFlag
 from utils import get_pin_index
 
 
@@ -11,19 +12,34 @@ class Audiocore:
         # PIO requires sideset pins to be adjacent
         assert get_pin_index(lrclk) == get_pin_index(dclk)+1 or get_pin_index(lrclk) == get_pin_index(dclk)-1
         self.notify = ThreadSafeFlag()
+        self.audiocore_lock = Lock()
         self._audiocore = _audiocore.Audiocore(din, dclk, lrclk, self._interrupt)
 
     def deinit(self):
+        assert not self.audiocore_lock.locked()
         self._audiocore.deinit()
 
     def _interrupt(self, _):
         self.notify.set()
 
     def flush(self):
+        assert not self.audiocore_lock.locked()
         self._audiocore.flush()
 
+    async def async_flush(self):
+        async with self.audiocore_lock:
+            self._audiocore.flush(False)
+            while True:
+                if self._audiocore.get_async_result() is not None:
+                    return
+                await self.notify.wait()
+
+    async def async_set_volume(self, volume):
+        async with self.audiocore_lock:
+            self._audiocore.set_volume(volume)
+
     def set_volume(self, volume):
-        self._audiocore.set_volume(volume)
+        asyncio.create_task(self.async_set_volume(volume))
 
     def put(self, buffer, blocking=False):
         pos = 0
diff --git a/software/modules/audiocore/module.c b/software/modules/audiocore/module.c
index c2cdbcb..881c65d 100644
--- a/software/modules/audiocore/module.c
+++ b/software/modules/audiocore/module.c
@@ -5,6 +5,8 @@
 
 // Include MicroPython API.
 #include "py/mperrno.h"
+#include "py/obj.h"
+#include "py/persistentcode.h"
 #include "py/runtime.h"
 #include "shared/runtime/mpirq.h"
 
@@ -61,6 +63,20 @@ static uint32_t get_fifo_read_value_blocking(struct audiocore_obj *obj)
     }
 }
 
+static bool get_fifo_read_value(struct audiocore_obj *obj, uint32_t *result)
+{
+    const long flags = save_and_disable_interrupts();
+    const uint32_t value = obj->fifo_read_value;
+    obj->fifo_read_value = 0;
+    if (value & AUDIOCORE_FIFO_DATA_FLAG) {
+        restore_interrupts(flags);
+        *result = value & ~AUDIOCORE_FIFO_DATA_FLAG;
+        return true;
+    }
+    restore_interrupts(flags);
+    return false;
+}
+
 /*
  * audiocore.Context.deinit(self)
  *
@@ -125,15 +141,31 @@ static MP_DEFINE_CONST_FUN_OBJ_2(audiocore_put_obj, audiocore_put);
  * Tells the audiocore to stop playback as soon as all MP3 frames still in the buffer have been decoded.
  * This function blocks until playback has ended.
  */
-static mp_obj_t audiocore_flush(mp_obj_t self_in)
+static mp_obj_t audiocore_flush(size_t n_args, const mp_obj_t *args)
 {
-    struct audiocore_obj *self = MP_OBJ_TO_PTR(self_in);
+    struct audiocore_obj *self = MP_OBJ_TO_PTR(args[0]);
+    mp_obj_t blocking = MP_ROM_TRUE;
+    if (n_args == 2) {
+        blocking = args[1];
+    }
     multicore_fifo_push_blocking(AUDIOCORE_CMD_FLUSH);
     wake_core1();
-    get_fifo_read_value_blocking(self);
+    if (mp_obj_is_true(blocking))
+        get_fifo_read_value_blocking(self);
     return mp_const_none;
 }
-static MP_DEFINE_CONST_FUN_OBJ_1(audiocore_flush_obj, audiocore_flush);
+static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audiocore_flush_obj, 1, 2, audiocore_flush);
+
+static mp_obj_t audiocore_get_async_result(mp_obj_t self_in)
+{
+    uint32_t result;
+    struct audiocore_obj *self = MP_OBJ_TO_PTR(self_in);
+    if (get_fifo_read_value(self, &result)) {
+        return mp_obj_new_int(result);
+    }
+    return mp_const_none;
+}
+static MP_DEFINE_CONST_FUN_OBJ_1(audiocore_get_async_result_obj, audiocore_get_async_result);
 
 /*
  * audiocore.set_volume(self, volume)
@@ -240,6 +272,7 @@ static const mp_rom_map_elem_t audiocore_locals_dict_table[] = {
     {MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&audiocore_deinit_obj)},
     {MP_ROM_QSTR(MP_QSTR_put), MP_ROM_PTR(&audiocore_put_obj)},
     {MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&audiocore_flush_obj)},
+    {MP_ROM_QSTR(MP_QSTR_get_async_result), MP_ROM_PTR(&audiocore_get_async_result_obj)},
     {MP_ROM_QSTR(MP_QSTR_set_volume), MP_ROM_PTR(&audiocore_set_volume_obj)},
 };
 static MP_DEFINE_CONST_DICT(audiocore_locals_dict, audiocore_locals_dict_table);
diff --git a/software/src/mp3player.py b/software/src/mp3player.py
index f62e156..1682fd7 100644
--- a/software/src/mp3player.py
+++ b/software/src/mp3player.py
@@ -74,7 +74,7 @@ class MP3Player:
             # Call onPlaybackDone after flush
             send_done = True
         finally:
-            self.audiocore.flush()
+            await self.audiocore.async_flush()
         if send_done:
             # Only call onPlaybackDone if exit due to end of stream
             # Use timer with time 0 to call callback "immediately" but from a different task