Index: rockbox/apps/dsp.h
===================================================================
RCS file: /cvsroot/rockbox/apps/dsp.h,v
retrieving revision 1.18
diff -u -r1.18 dsp.h
--- rockbox/apps/dsp.h	22 Apr 2006 14:40:12 -0000	1.18
+++ rockbox/apps/dsp.h	24 Aug 2006 20:21:21 -0000
@@ -31,6 +31,7 @@
 enum {
     CODEC_SET_FILEBUF_WATERMARK = 1,
     CODEC_SET_FILEBUF_CHUNKSIZE,
+    CODEC_SET_FILEBUF_PRESEEK,
     DSP_SET_FREQUENCY,
     DSP_SWITCH_FREQUENCY,
     DSP_SET_CLIP_MIN,
Index: rockbox/apps/playback.h
===================================================================
RCS file: /cvsroot/rockbox/apps/playback.h,v
retrieving revision 1.35
diff -u -r1.35 playback.h
--- rockbox/apps/playback.h	15 Aug 2006 12:27:04 -0000	1.35
+++ rockbox/apps/playback.h	24 Aug 2006 20:21:21 -0000
@@ -47,7 +47,7 @@
     size_t codecsize;          /* Codec length in bytes */
     bool has_codec;            /* Does this track have a codec on the buffer */
 
-    // size_t buf_idx;            /* Pointer to the track's buffer */
+    size_t buf_idx;            /* Pointer to the track's buffer */
     size_t filerem;            /* Remaining bytes of file NOT in buffer */
     size_t filesize;           /* File total length */
     size_t start_pos;          /* Position to first bytes of file in buffer */
Index: rockbox/apps/playback.c
===================================================================
RCS file: /cvsroot/rockbox/apps/playback.c,v
retrieving revision 1.343
diff -u -r1.343 playback.c
--- rockbox/apps/playback.c	23 Aug 2006 14:02:35 -0000	1.343
+++ rockbox/apps/playback.c	24 Aug 2006 20:21:21 -0000
@@ -262,6 +262,7 @@
 /* Configuration */
 static size_t conf_watermark;
 static size_t conf_filechunk;
+static size_t conf_preseek;
 static size_t buffer_margin;
 
 static bool v1first = false;
@@ -952,11 +953,12 @@
     filling = false;
 
     /* Reset buffer and track pointers */
-    buf_ridx = buf_widx = 0;
+    tracks[track_ridx].buf_idx = buf_ridx = buf_widx = 0;
     track_widx = track_ridx;
     cur_ti = &tracks[track_ridx];
     audio_clear_track_entries(true, true, false);
     filebufused = 0;
+    cur_ti->available = 0;
 
     /* Fill the buffer */
     last_peek_offset = -1;
@@ -1133,16 +1135,16 @@
     /* Clear codec buffer. */
     track_widx = track_ridx;
     filebufused = 0;
-    buf_widx = buf_ridx = 0;
+    tracks[track_widx].buf_idx = buf_widx = buf_ridx = 0;
 
     last_peek_offset = 0;
     filling = false;
     initialize_buffer_fill(true);
+    filling = true;
 
-    if (newpos > AUDIO_REBUFFER_GUESS_SIZE) 
-    {
-        buf_ridx += AUDIO_REBUFFER_GUESS_SIZE;
-        cur_ti->start_pos = newpos - AUDIO_REBUFFER_GUESS_SIZE;
+    if (newpos > conf_preseek) {
+        buf_ridx += conf_preseek;
+        cur_ti->start_pos = newpos - conf_preseek;
     } 
     else 
     {
@@ -1341,6 +1343,10 @@
         conf_filechunk = (unsigned long)value;
         break;
 
+    case CODEC_SET_FILEBUF_PRESEEK:
+        conf_preseek = (unsigned long)value;
+        break;
+
     default:
         if (!dsp_configure(setting, value)) { logf("Illegal key:%d", setting); }
     }
@@ -1465,8 +1471,18 @@
         }
 
         buf_widx += rc;
+
+        int overlap = buf_widx - tracks[track_ridx].buf_idx;
         if (buf_widx >= filebuflen)
             buf_widx -= filebuflen;
+        if (overlap >= filebuflen)
+            overlap -= filebuflen;
+
+        if (overlap > 0 && overlap <= rc && tracks[track_ridx].available != 0) {
+            tracks[track_ridx].buf_idx = buf_widx;
+            tracks[track_ridx].start_pos += overlap;
+        }
+        
         tracks[track_widx].available += rc;
         tracks[track_widx].filerem -= rc;
 
@@ -1775,6 +1791,7 @@
         current_codec = CODEC_IDX_AUDIO;
         conf_watermark = AUDIO_DEFAULT_WATERMARK;
         conf_filechunk = AUDIO_DEFAULT_FILECHUNK;
+        conf_preseek = AUDIO_REBUFFER_GUESS_SIZE;
         dsp_configure(DSP_RESET, 0);
         current_codec = last_codec;
     }
@@ -1886,7 +1903,7 @@
     }
     
     logf("alt:%s", trackname);
-    // tracks[track_widx].buf_idx = buf_widx;
+    tracks[track_widx].buf_idx = buf_widx;
 
     audio_read_file(rebuffer);