diff --git a/audio/out/ao_avfoundation.m b/audio/out/ao_avfoundation.m
index 887ec7ce33b91..c6faf65a05896 100644
--- a/audio/out/ao_avfoundation.m
+++ b/audio/out/ao_avfoundation.m
@@ -61,16 +61,16 @@ static CMTime CMTimeFromNanoseconds(int64_t time)
 static void feed(struct ao *ao)
 {
     struct priv *p = ao->priv;
+    int samplerate = ao->samplerate;
+    int sstride = ao->sstride;
+
     CMBlockBufferRef block_buffer = NULL;
     CMSampleBufferRef sample_buffer = NULL;
+    OSStatus err;
 
-    int64_t cur_time_av = CMTimeGetNanoseconds([p->synchronizer currentTime]);
-    int64_t cur_time_mp = mp_time_ns();
-    p->end_time_av = MPMAX(p->end_time_av, cur_time_av);
-
-    int request_sample_count = ao->samplerate / 10; // 1/10 samplerate may be a good number
-    int buffer_size = request_sample_count * ao->sstride;
-    if (CMBlockBufferCreateWithMemoryBlock(
+    int request_sample_count = samplerate / 10;
+    int buffer_size = request_sample_count * sstride;
+    if ((err = CMBlockBufferCreateWithMemoryBlock(
         kCFAllocatorDefault,
         NULL,
         buffer_size,
@@ -80,30 +80,36 @@ static void feed(struct ao *ao)
         buffer_size,
         kCMBlockBufferAssureMemoryNowFlag,
         &block_buffer
-    ) != noErr) {
-        MP_FATAL(ao, "failed to create CMBlockBuffer\n");
+    )) != noErr) {
+        MP_FATAL(ao, "failed to create block buffer\n");
+        MP_VERBOSE(ao, "CMBlockBufferCreateWithMemoryBlock returned %d\n", err);
         goto error;
     }
     void* data[1];
-    if (CMBlockBufferGetDataPointer(block_buffer, 0, NULL, NULL, (char**)data) != noErr) {
-        MP_FATAL(ao, "CMBlockBufferGetDataPointer failed\n");
+    if ((err = CMBlockBufferGetDataPointer(block_buffer, 0, NULL, NULL, (char**)data)) != noErr) {
+        MP_FATAL(ao, "failed to get data pointer from block buffer\n");
+        MP_VERBOSE(ao, "CMBlockBufferGetDataPointer returned %d\n", err);
         goto error;
     }
 
-    int64_t delta = CMTimeGetNanoseconds(CMTimeMake(request_sample_count, ao->samplerate));
-    int real_sample_count = ao_read_data_nonblocking(ao, data, request_sample_count, p->end_time_av - cur_time_av + cur_time_mp + delta);
+    int64_t cur_time_av = CMTimeGetNanoseconds([p->synchronizer currentTime]);
+    int64_t cur_time_mp = mp_time_ns();
+    int64_t end_time_av = MPMAX(p->end_time_av, cur_time_av);
+    int64_t time_delta = CMTimeGetNanoseconds(CMTimeMake(request_sample_count, samplerate));
+    int real_sample_count = ao_read_data_nonblocking(ao, data, request_sample_count, end_time_av - cur_time_av + cur_time_mp + time_delta);
     if (real_sample_count == 0) {
-        mp_sleep_ns(1000000); // avoid spinning
+        // avoid spinning by blocking the thread.
+        mp_sleep_ns(1000000);
         goto finish;
     }
 
     CMSampleTimingInfo sample_timing_into[] = {(CMSampleTimingInfo) {
-        .duration = CMTimeMake(1, ao->samplerate),
-        .presentationTimeStamp = CMTimeFromNanoseconds(p->end_time_av),
+        .duration = CMTimeMake(1, samplerate),
+        .presentationTimeStamp = CMTimeFromNanoseconds(end_time_av),
         .decodeTimeStamp = kCMTimeInvalid
     }};
-    size_t sample_size_array[] = {ao->sstride};
-    if (CMSampleBufferCreateReady(
+    size_t sample_size_array[] = {sstride};
+    if ((err = CMSampleBufferCreateReady(
         kCFAllocatorDefault,
         block_buffer,
         p->format_description,
@@ -113,15 +119,16 @@ static void feed(struct ao *ao)
         1,
         sample_size_array,
         &sample_buffer
-    ) != noErr) {
-        MP_FATAL(ao, "failed to create CMSampleBuffe\n");
+    )) != noErr) {
+        MP_FATAL(ao, "failed to create sample buffer\n");
+        MP_VERBOSE(ao, "CMSampleBufferCreateReady returned %d\n", err);
         goto error;
     }
 
     [p->renderer enqueueSampleBuffer:sample_buffer];
 
-    delta = CMTimeGetNanoseconds(CMTimeMake(real_sample_count, ao->samplerate));
-    p->end_time_av += delta;
+    time_delta = CMTimeGetNanoseconds(CMTimeMake(real_sample_count, samplerate));
+    p->end_time_av = end_time_av + time_delta;
 
     goto finish;
 
@@ -162,21 +169,16 @@ static int control(struct ao *ao, enum aocontrol cmd, void *arg)
     case AOCONTROL_GET_MUTE:
         *(bool*)arg = [p->renderer isMuted];
         return CONTROL_OK;
-
     case AOCONTROL_GET_VOLUME:
         *(float*)arg = [p->renderer volume] * 100;
         return CONTROL_OK;
-
     case AOCONTROL_SET_MUTE:
         [p->renderer setMuted:*(bool*)arg];
         return CONTROL_OK;
-
     case AOCONTROL_SET_VOLUME:
         [p->renderer setVolume:*(float*)arg / 100];
         return CONTROL_OK;
-
     default:
-        // AOCONTROL_UPDATE_STREAM_TITLE should be handled by remote_command_center.swift
         return CONTROL_UNKNOWN;
     }
 }
@@ -211,11 +213,13 @@ static int init(struct ao *ao)
 #endif
 
     if ((p->renderer = [[AVSampleBufferAudioRenderer alloc] init]) == nil) {
-        MP_FATAL(ao, "failed to create AVSampleBufferAudioRenderer\n");
+        MP_FATAL(ao, "failed to create audio renderer\n");
+        MP_VERBOSE(ao, "AVSampleBufferAudioRenderer failed to initialize\n");
         goto error;
     }
     if ((p->synchronizer = [[AVSampleBufferRenderSynchronizer alloc] init]) == nil) {
-        MP_FATAL(ao, "failed to create AVSampleBufferRenderSynchronizer\n");
+        MP_FATAL(ao, "failed to create rendering synchronizer\n");
+        MP_VERBOSE(ao, "AVSampleBufferRenderSynchronizer failed to initialize\n");
         goto error;
     }
     if ((p->queue = dispatch_queue_create(
@@ -223,6 +227,7 @@ static int init(struct ao *ao)
         dispatch_queue_attr_make_with_qos_class(DISPATCH_QUEUE_SERIAL, QOS_CLASS_USER_INTERACTIVE, 0)
     )) == NULL) {
         MP_FATAL(ao, "failed to create dispatch queue\n");
+        MP_VERBOSE(ao, "dispatch_queue_create failed\n");
         goto error;
     }
 
@@ -269,7 +274,8 @@ static int init(struct ao *ao)
     talloc_free(talloc_ctx);
     ca_log_layout(ao, MSGL_V, layout);
 
-    if (CMAudioFormatDescriptionCreate(
+    OSStatus err;
+    if ((err = CMAudioFormatDescriptionCreate(
         kCFAllocatorDefault,
         &asbd,
         layout_size,
@@ -278,8 +284,9 @@ static int init(struct ao *ao)
         NULL,
         NULL,
         &p->format_description
-    ) != noErr) {
-        MP_FATAL(ao, "failed to create CMAudioFormatDescription\n");
+    )) != noErr) {
+        MP_FATAL(ao, "failed to create audio format description\n");
+        MP_VERBOSE(ao, "CMAudioFormatDescriptionCreate returned %d\n", err);
         goto error;
     }
     talloc_free(layout);