(gdb) bt
#0  0x0091218b in malloc_consolidate () from /lib/tls/libc.so.6
#1  0x009131c3 in _int_malloc () from /lib/tls/libc.so.6
#2  0x00914f81 in malloc () from /lib/tls/libc.so.6
#3  0x002efc62 in lintoulaw_new () at codec_ulaw.c:127
#4  0x0806ae3e in ast_translator_build_path (dest=4, source=6) at translate.c:141
#5  0x08062f7a in set_format (chan=0xb7aa1d30, fmt=64, rawformat=0xb7aa2128, format=0xb7aa1e58, trans=0xb7aa211c, direction=1)
    at channel.c:2352
#6  0x08063126 in ast_set_write_format (chan=0x62696c2f, fmt=1920169263) at channel.c:2368
#7  0x00550b7f in moh_files_generator (chan=0xb7aa1d30, data=0x9b746c0, len=160, samples=160) at res_musiconhold.c:220
#8  0x08065a2a in ast_read (chan=0xb7aa1d30) at channel.c:1986
#9  0x00e55998 in try_calling (qe=0xb7726b50, options=Variable "options" is not available.
) at app_queue.c:1824
#10 0x00e5897c in queue_exec (chan=0xb7aa1d30, data=0xb772b0a0) at app_queue.c:3009
#11 0x08090abd in pbx_extension_helper (c=0xb7aa1d30, con=Variable "con" is not available.
) at pbx.c:544
#12 0x08091d86 in __ast_pbx_run (c=0xb7aa1d30) at pbx.c:2218
#13 0x0809383c in pbx_thread (data=0x62696c2f) at pbx.c:2505
#14 0x00a8c341 in start_thread () from /lib/tls/libpthread.so.0
#15 0x009786fe in clone () from /lib/tls/libc.so.6
(gdb)