Index: apps/playback.c
===================================================================
--- apps/playback.c	(revisione 23221)
+++ apps/playback.c	(copia locale)
@@ -2468,6 +2468,9 @@
  */
 static void audio_reset_buffer(void)
 {
+    /* prevent any further use of buffer_alloc */
+    buffer_lock();
+
     /* see audio_get_recording_buffer if this is modified */
     logf("audio_reset_buffer");
 
@@ -2741,8 +2744,8 @@
     pcmbuf_crossfade_enable(global_settings.crossfade);
 
     /* initialize the buffering system */
+    buffering_init();
 
-    buffering_init();
     /* ...now! Set up the buffers */
     audio_reset_buffer();
 
Index: firmware/export/buffer.h
===================================================================
--- firmware/export/buffer.h	(revisione 23221)
+++ firmware/export/buffer.h	(copia locale)
@@ -32,5 +32,6 @@
 
 void buffer_init(void);
 void *buffer_alloc(size_t size);
+void buffer_lock(void);
 
 #endif
Index: firmware/common/dircache.c
===================================================================
--- firmware/common/dircache.c	(revisione 23221)
+++ firmware/common/dircache.c	(copia locale)
@@ -550,7 +550,7 @@
 /**
  * Internal function which scans the disk and creates the dircache structure.
  */
-static int dircache_do_rebuild(void)
+static int dircache_do_rebuild(bool allowbufferalloc)
 {
 #ifdef SIMULATOR
     DIR_UNCACHED *pdir;
@@ -628,7 +628,7 @@
         dircache_bind(fdbind_cache[i].fd, fdbind_cache[i].path);
     fdbind_idx = 0;
     
-    if (thread_enabled)
+    if (!allowbufferalloc)
     {
         if (allocated_size - dircache_size < DIRCACHE_RESERVE)
             reserve_used = DIRCACHE_RESERVE - (allocated_size - dircache_size);
@@ -636,9 +636,8 @@
     else
     {
         /* We have to long align the audiobuf to keep the buffer access fast. */
-        audiobuf += (long)((dircache_size & ~0x03) + 0x04);
-        audiobuf += DIRCACHE_RESERVE;
         allocated_size = dircache_size + DIRCACHE_RESERVE;
+        buffer_alloc(allocated_size);
         reserve_used = 0;
     }
     
@@ -666,7 +665,7 @@
 #endif
             case DIRCACHE_BUILD:
                 thread_enabled = true;
-                dircache_do_rebuild();
+                dircache_do_rebuild(false);
                 thread_enabled = false;
                 break ;
                 
@@ -717,10 +716,10 @@
         return 3;
     }
 
-    dircache_root = (struct dircache_entry *)(((long)audiobuf & ~0x03) + 0x04);
+    dircache_root = (struct dircache_entry *) buffer_alloc(0); // 
 
     /* Start a non-transparent rebuild. */
-    return dircache_do_rebuild();
+    return dircache_do_rebuild(true);
 }
 
 /**
Index: firmware/buffer.c
===================================================================
--- firmware/buffer.c	(revisione 23221)
+++ firmware/buffer.c	(copia locale)
@@ -20,6 +20,7 @@
  ****************************************************************************/
 #include <stdio.h>
 #include "buffer.h"
+#include "panic.h"
 
 #ifdef SIMULATOR
 unsigned char audiobuffer[(MEM*1024-256)*1024];
@@ -30,15 +31,20 @@
 #endif
 
 unsigned char *audiobuf;
+static int locked;
 
 void buffer_init(void)
 {
     /* 32-bit aligned */
     audiobuf = (void *)(((unsigned long)audiobuffer + 3) & ~3);
+    locked = 0;
 }
 
 void *buffer_alloc(size_t size)
 {
+    if (locked != 0)
+        panicf("Attempt to resize audio buffer whilst in use. size=%lu", size);
+
     void *retval = audiobuf;
     
     audiobuf += size;
@@ -48,3 +54,7 @@
     return retval;
 }
 
+void buffer_lock(void)
+{
+    locked = 1;
+}