Index: ../apps/buffering.c
===================================================================
--- ../apps/buffering.c	(revision 17971)
+++ ../apps/buffering.c	(working copy)
@@ -813,19 +813,26 @@
    Return whether or not to continue filling after this */
 static bool fill_buffer(void)
 {
+    struct memory_handle *m;
     logf("fill_buffer()");
-    struct memory_handle *m = first_handle;
-    shrink_handle(m);
+    shrink_handle(first_handle);
+    mutex_lock(&llist_mutex);
+    m = first_handle;
     while (queue_empty(&buffering_queue) && m) {
         if (m->filerem > 0) {
+            mutex_unlock(&llist_mutex);
             if (!buffer_handle(m->id)) {
                 m = NULL;
                 break;
             }
+            mutex_lock(&llist_mutex);
+            m = first_handle;
         }
         m = m->next;
     }
 
+    mutex_unlock(&llist_mutex);
+
     if (m) {
         return true;
     }
@@ -924,10 +931,12 @@
     if (adjusted_offset > size)
         adjusted_offset = 0;
 
+    mutex_lock(&llist_mutex);
     struct memory_handle *h = add_handle(size-adjusted_offset, can_wrap, false);
     if (!h)
     {
         DEBUGF("bufopen: failed to add handle\n");
+        mutex_unlock(&llist_mutex);
         close(fd);
         return ERR_BUFFER_FULL;
     }
@@ -943,7 +952,6 @@
     {
         /* Bitmap file: we load the data instead of the file */
         int rc;
-        mutex_lock(&llist_mutex); /* Lock because load_bitmap yields */
         rc = load_bitmap(fd);
         if (rc <= 0)
         {
@@ -957,7 +965,6 @@
         h->available = rc;
         h->widx = buf_widx + rc; /* safe because the data doesn't wrap */
         buf_widx += rc;  /* safe too */
-        mutex_unlock(&llist_mutex);
     }
     else
 #endif
@@ -968,6 +975,8 @@
         h->widx = buf_widx;
     }
 
+    mutex_unlock(&llist_mutex);
+
     if (type == TYPE_CUESHEET) {
         h->fd = fd;
         /* Immediately start buffering those */
@@ -1319,7 +1328,9 @@
 static void shrink_buffer(void)
 {
     logf("shrink_buffer()");
+    mutex_lock(&llist_mutex);
     shrink_buffer_inner(first_handle);
+    mutex_unlock(&llist_mutex);
 }
 
 void buffering_thread(void)