(gdb) bt
#0  0x40017410 in ?? ()
#1  0x42fb2dd8 in ?? ()
#2  0x00000006 in ?? ()
#3  0x00006479 in ?? ()
#4  0x40211811 in raise () from /lib/tls/i686/cmov/libc.so.6
#5  0x40212fb9 in abort () from /lib/tls/i686/cmov/libc.so.6
#6  0x4020afbf in __assert_fail () from /lib/tls/i686/cmov/libc.so.6
#7  0x400279fa in switch_buffer_inuse ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#8  0x4002bb2f in switch_channel_has_dtmf ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#9  0x400315b2 in switch_core_session_reset ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#10 0x400444b4 in audio_bridge_thread ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#11 0x40044900 in audio_bridge_on_loopback ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#12 0x40036a20 in switch_core_session_run ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#13 0x40038131 in switch_core_session_thread ()
   from /usr/local/freeswitch/lib/libfreeswitch.so.1
#14 0x4009d478 in dummy_worker () from /usr/local/freeswitch/lib/libapr-1.so.0
#15 0x401c0240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
---Type <return> to continue, or q <return> to quit---
#16 0x402b432e in clone () from /lib/tls/i686/cmov/libc.so.6