(gdb) bt
#0  ast_rtp_write (rtp=0x31202f2045544956, _f=0x42532f00) at rtp.c:2875
#1  0x00007f9297996952 in sip_write (ast=0x14e6360, frame=0x42532f00) at chan_sip.c:3922
#2  0x00007f9297996c55 in sip_rtp_prod (data=<value optimized out>) at chan_sip.c:4650
#3  0x00000000004a92db in ast_sched_runq (con=<value optimized out>) at sched.c:363
#4  0x00007f92979800fa in do_monitor (data=<value optimized out>) at chan_sip.c:17082
#5  0x00000000004b6c7c in dummy_start (data=<value optimized out>) at utils.c:856
#6  0x00007f92af75bfc7 in start_thread () from /lib/libpthread.so.0
#7  0x00007f92aedfb5ad in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()
(gdb) bt full
#0  ast_rtp_write (rtp=0x31202f2045544956, _f=0x42532f00) at rtp.c:2875
	f = <value optimized out>
	codec = <value optimized out>
	subclass = <value optimized out>
	__PRETTY_FUNCTION__ = "ast_rtp_write"
#1  0x00007f9297996952 in sip_write (ast=0x14e6360, frame=0x42532f00) at chan_sip.c:3922
	p = (struct sip_pvt *) 0x14f0800
	res = <value optimized out>
	__PRETTY_FUNCTION__ = "sip_write"
#2  0x00007f9297996c55 in sip_rtp_prod (data=<value optimized out>) at chan_sip.c:4650
	chan = (struct ast_channel *) 0x14e6360
	a = {frametype = AST_FRAME_VOICE, subclass = 8, datalen = 160, samples = 160, mallocd = 0, mallocd_hdr_len = 0, offset = 0, src = 0x7f92979a3dd5 "sip_rtp_prod", data = 0x42532e60, delivery = {tv_sec = 0, tv_usec = 0}, 
  frame_list = {next = 0x0}, flags = 1, ts = 12345, len = 20, seqno = 12345}
	garbage = '\0' <repeats 48 times>, "Q\231:\ufffd", '\0' <repeats 12 times>, "j\ufffd\226<", '\0' <repeats 12 times>, "\ufffd\034\ufffd9", '\0' <repeats 12 times>, "'\u03f1<", '\0' <repeats 12 times>, "\ufffd\ufffd\031:", '\0' <repeats 12 times>, "\037tV<", '\0' <repeats 27 times>
	__PRETTY_FUNCTION__ = "sip_rtp_prod"
#3  0x00000000004a92db in ast_sched_runq (con=<value optimized out>) at sched.c:363
	tv = {tv_sec = 1271414078, tv_usec = 335489}
	numevents = 0
	res = 0
#4  0x00007f92979800fa in do_monitor (data=<value optimized out>) at chan_sip.c:17082
	res = <value optimized out>
	sip = (struct sip_pvt *) 0x0
	t = 1271414077
	fastrestart = 0
	lastpeernum = -1
	curpeernum = <value optimized out>
	reloading = 1271414077
	__PRETTY_FUNCTION__ = "do_monitor"
#5  0x00000000004b6c7c in dummy_start (data=<value optimized out>) at utils.c:856
	__cancel_buf = {__cancel_jmp_buf = {{__cancel_jmp_buf = {140267861599840, 7812870177540275435, 140736279957136, 140267985682176, 0, 4096, 7812725755527822571, 7812870824599485675}, __mask_was_saved = 0}}, __pad = {0x425331e0, 
    0x0, 0x0, 0x0}}
	not_first_call = <value optimized out>
	ret = <value optimized out>
#6  0x00007f92af75bfc7 in start_thread () from /lib/libpthread.so.0
No symbol table info available.
#7  0x00007f92aedfb5ad in clone () from /lib/libc.so.6
No symbol table info available.
#8  0x0000000000000000 in ?? ()
No symbol table info available.