(gdb) bt
#0  0x00bea7a2 in _dl_sysinfo_int80 () from /lib/ld-linux.so.2
#1  0x00c2b825 in raise () from /lib/tls/libc.so.6
#2  0x00c2d289 in abort () from /lib/tls/libc.so.6
#3  0x00c5fcda in __libc_message () from /lib/tls/libc.so.6
#4  0x00c6656f in _int_free () from /lib/tls/libc.so.6
#5  0x00c6694a in free () from /lib/tls/libc.so.6
#6  0x00c6328b in _IO_free_backup_area_internal () from /lib/tls/libc.so.6
#7  0x00c635b4 in __underflow () from /lib/tls/libc.so.6
#8  0x00c62b23 in _IO_file_xsgetn_internal () from /lib/tls/libc.so.6
#9  0x00c639e8 in _IO_sgetn_internal () from /lib/tls/libc.so.6
#10 0x00c57c19 in fread () from /lib/tls/libc.so.6
#11 0x004816cb in wav_read (s=0xb5c15218, whennext=0x0) at format_wav.c:378
#12 0x0809ddf3 in ast_readaudio_callback (s=0xb5c15218) at file.c:740
#13 0x0809df1e in ast_fsread_audio (data=0x0) at file.c:791
#14 0x080f510a in ast_sched_runq (con=0x854a9b8) at sched.c:363
#15 0x0809f192 in waitstream_core (c=0x86f3200, breakon=Variable "breakon" is not available.
) at file.c:1289
#16 0x0809f74c in ast_waitstream (c=0x0, breakon=0x6 "") at file.c:1305
#17 0x0023e738 in agent_call (ast=0xb5e05e48, dest=0xb77f8496 "4929", timeout=0) at chan_agent.c:764
#18 0x0808030e in ast_call (chan=0xb5e05e48, addr=0x0, timeout=0) at channel.c:3407
#19 0x002f126b in ring_entry (qe=0xb77fa840, tmp=0xb5ed1228, busies=0xb77f87a4) at app_queue.c:1985
#20 0x002f1a9c in ring_one (qe=0xb77fa840, outgoing=0xb5ed1228, busies=0xb77f87a4) at app_queue.c:2063
#21 0x002f2d45 in try_calling (qe=0xb77fa840, options=Variable "options" is not available.
) at app_queue.c:2954
#22 0x002f8265 in queue_exec (chan=0xb5e052f8, data=0xb77fac70) at app_queue.c:4077
#23 0x080c30ef in pbx_exec (c=0xb5e052f8, app=0x84e5e20, data=0xb77fac70)
    at /usr/src/asterisk/asterisk-1.4.26/include/asterisk/strings.h:36
#24 0x00263462 in realtime_exec (chan=0xb5e052f8, context=0xb5e05478 "default", exten=0xb5e054c8 "14929", priority=2, 
    callerid=0xb5e68dc0 "0555425587", data=0x84db35d "@") at pbx_realtime.c:216
#25 0x080caae8 in pbx_extension_helper (c=0xb5e052f8, con=Variable "con" is not available.
) at pbx.c:1874
#26 0x080cf246 in __ast_pbx_run (c=0xb5e052f8) at pbx.c:2283
#27 0x080d118e in pbx_thread (data=0xb5e052f8) at pbx.c:2599
#28 0x08102755 in dummy_start (data=0x6) at utils.c:856
#29 0x00d653cc in start_thread () from /lib/tls/libpthread.so.0
#30 0x00ccf96e in clone () from /lib/tls/libc.so.6