#0  0x00c66909 in free () from /lib/tls/libc.so.6
(gdb) bt
#0  0x00c66909 in free () from /lib/tls/libc.so.6
#1  0x00c6328b in _IO_free_backup_area_internal () from /lib/tls/libc.so.6
#2  0x00c635b4 in __underflow () from /lib/tls/libc.so.6
#3  0x00c62b23 in _IO_file_xsgetn_internal () from /lib/tls/libc.so.6
#4  0x00c639e8 in _IO_sgetn_internal () from /lib/tls/libc.so.6
#5  0x00c57c19 in fread () from /lib/tls/libc.so.6
#6  0x002b06cb in wav_read (s=0x9ad9750, whennext=0xd30804) at format_wav.c:378
#7  0x0809de53 in ast_readaudio_callback (s=0x9ad9750) at file.c:752
#8  0x0809df7e in ast_fsread_audio (data=0xd30804) at file.c:803
#9  0x080f517a in ast_sched_runq (con=0x994a598) at sched.c:363
#10 0x0809f202 in waitstream_core (c=0x9a85990, breakon=Variable "breakon" is not available.
) at file.c:1301
#11 0x0809f7bc in ast_waitstream (c=0xd30804, breakon=0x0) at file.c:1317
#12 0x00829738 in agent_call (ast=0x99dc348, dest=0xb607c496 "4301", timeout=0) at chan_agent.c:764
#13 0x0808030e in ast_call (chan=0x99dc348, addr=0xd30804 "", timeout=13830148) at channel.c:3407
#14 0x0022b26b in ring_entry (qe=0xb607e840, tmp=0x9cdd0a8, busies=0xb607c7a4) at app_queue.c:1985
#15 0x0022ba9c in ring_one (qe=0xb607e840, outgoing=0x9cdd0a8, busies=0xb607c7a4) at app_queue.c:2063
#16 0x0022cd45 in try_calling (qe=0xb607e840, options=Variable "options" is not available.
) at app_queue.c:2954
#17 0x00232265 in queue_exec (chan=0xb7d1cd90, data=0xb607ec70) at app_queue.c:4077
#18 0x080c315f in pbx_exec (c=0xb7d1cd90, app=0x990a0a0, data=0xb607ec70)
    at /usr/src/asterisk/asterisk-1.4.26/include/asterisk/strings.h:36
#19 0x001d4462 in realtime_exec (chan=0xb7d1cd90, context=0xb7d1cf10 "default", exten=0xb7d1cf60 "14301", priority=2, 
    callerid=0xb7dc9500 "Unknown", data=0x98ff2e5 "@") at pbx_realtime.c:216
#20 0x080cab58 in pbx_extension_helper (c=0xb7d1cd90, con=Variable "con" is not available.
) at pbx.c:1874
#21 0x080cf2b6 in __ast_pbx_run (c=0xb7d1cd90) at pbx.c:2283
#22 0x080d11fe in pbx_thread (data=0xb7d1cd90) at pbx.c:2599
#23 0x081027c5 in dummy_start (data=0x0) at utils.c:856
#24 0x00d653cc in start_thread () from /lib/tls/libpthread.so.0
#25 0x00ccf96e in clone () from /lib/tls/libc.so.6

(gdb) frame 7
#7  0x0809de53 in ast_readaudio_callback (s=0x9ad9750) at file.c:752
752                     fr = s->fmt->read(s, &whennext);
(gdb) print *s
$3 = {fmt = 0x99158a8, flags = 0, mode = 0, filename = 0x0, realfilename = 0x0, vfs = 0x0, trans = 0x0, tr = 0x0, 
  lastwriteformat = 0, lasttimeout = 160, owner = 0x9a85990, f = 0x9baf9d8, fr = {frametype = AST_FRAME_VOICE, 
    subclass = 64, datalen = 320, samples = 160, mallocd = 0, mallocd_hdr_len = 0, offset = 64, src = 0x99158a8 "wav", 
    data = 0x9ada80c, delivery = {tv_sec = 0, tv_usec = 0}, frame_list = {next = 0x0}, flags = 0, ts = 0, len = 0, 
    seqno = 0}, buf = 0x9ada7cc "", {_private = 0x9ada94c, private = 0x9ada94c}, orig_chan_name = 0x0, 
  big_waste_of_memory = '\0' <repeats 4095 times>}