#0  0x00002b88ffe8dee5 in raise () from /lib/libc.so.6
#1  0x00002b88ffe8f403 in abort () from /lib/libc.so.6
#2  0x00002b88ff9ca4b0 in IA__g_logv (log_domain=0x2b88fdeb7654 "GStreamer", log_level=G_LOG_LEVEL_CRITICAL, 
    format=0x2b88ff9f960d "%s: assertion `%s' failed", args1=0x4600a8b0)
    at /build/buildd/glib2.0-2.14.6/glib/gmessages.c:497
#3  0x00002b88ff9ca533 in IA__g_log (log_domain=0x6eaf <Address 0x6eaf out of bounds>, log_level=28489, 
    format=0x6 <Address 0x6 out of bounds>) at /build/buildd/glib2.0-2.14.6/glib/gmessages.c:517
#4  0x00002aaab38b1c3c in gst_speex_enc_chain (pad=<value optimized out>, buf=0x7b5700) at gstspeexenc.c:879
#5  0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x9272e0, buffer=0x7b5700) at gstpad.c:3518
#6  0x00002b88fde825a3 in gst_pad_push (pad=0x874e30, buffer=0x7b5700) at gstpad.c:3686
#7  0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x8d7d80, buffer=0x7b5700) at gstpad.c:3518
#8  0x00002b88fde825a3 in gst_pad_push (pad=0x8ebe60, buffer=0x7b5700) at gstpad.c:3686
#9  0x00002b8906740f2a in gst_base_transform_chain (pad=<value optimized out>, buffer=<value optimized out>)
    at gstbasetransform.c:1615
#10 0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x8ebcf0, buffer=0x943030) at gstpad.c:3518
#11 0x00002b88fde825a3 in gst_pad_push (pad=0x927170, buffer=0x943030) at gstpad.c:3686
#12 0x00002b8906740f2a in gst_base_transform_chain (pad=<value optimized out>, buffer=<value optimized out>)
    at gstbasetransform.c:1615
#13 0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x927000, buffer=0x943030) at gstpad.c:3518
#14 0x00002b88fde825a3 in gst_pad_push (pad=0x77b510, buffer=0x943030) at gstpad.c:3686
#15 0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x77c650, buffer=0x943030) at gstpad.c:3518
#16 0x00002b88fde825a3 in gst_pad_push (pad=0x79f730, buffer=0x943030) at gstpad.c:3686
#17 0x00002b8906740f2a in gst_base_transform_chain (pad=<value optimized out>, buffer=<value optimized out>)
    at gstbasetransform.c:1615
#18 0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x79f5c0, buffer=0x943030) at gstpad.c:3518
#19 0x00002b88fde825a3 in gst_pad_push (pad=0x77b360, buffer=0x943030) at gstpad.c:3686
#20 0x00002b88fde81f89 in gst_pad_chain_unchecked (pad=0x77c4c0, buffer=0x943030) at gstpad.c:3518
#21 0x00002b88fde825a3 in gst_pad_push (pad=0x79f450, buffer=0x943030) at gstpad.c:3686
#22 0x00002b890673c19c in gst_base_src_loop (pad=0x79f450) at gstbasesrc.c:2111
#23 0x00002b88fde9af09 in gst_task_func (task=0x754500, tclass=<value optimized out>) at gsttask.c:192
#24 0x00002b88ff9e53d7 in g_thread_pool_thread_proxy (data=<value optimized out>)
    at /build/buildd/glib2.0-2.14.6/glib/gthreadpool.c:265
#25 0x00002b88ff9e3864 in g_thread_create_proxy (data=0x93fc90)
    at /build/buildd/glib2.0-2.14.6/glib/gthread.c:635
#26 0x00002b88ffc45fc7 in start_thread () from /lib/libpthread.so.0
#27 0x00002b88fff2b29d in clone () from /lib/libc.so.6
#28 0x0000000000000000 in ?? ()
(gdb)