no space in ardour-UI request buffer for thread unknown

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1236539728 (LWP 21202)]
0xb6d63377 in sigc::internal::trackable_callback_list::remove_callback (
    this=0x9566070, data=0xa0791c8) at libs/sigc++2/sigc++/trackable.cc:114
114         if ((*i).data_ == data)
(gdb) thread apply all bt

Thread 7 (Thread -1330263136 (LWP 21242)):
#0  0xb72be894 in gdk_region_intersect () from /usr/lib/libgdk-x11-2.0.so.0
#1  0xb72c27b6 in gdk_window_invalidate_maybe_recurse ()
   from /usr/lib/libgdk-x11-2.0.so.0
#2  0xb72c27b6 in gdk_window_invalidate_maybe_recurse ()
   from /usr/lib/libgdk-x11-2.0.so.0
#3  0xb72c2910 in gdk_window_invalidate_region ()
   from /usr/lib/libgdk-x11-2.0.so.0
#4  0xb72c29cf in gdk_window_invalidate_rect ()
   from /usr/lib/libgdk-x11-2.0.so.0
#5  0xb756eca0 in gtk_widget_queue_draw_area ()
   from /usr/lib/libgtk-x11-2.0.so.0
#6  0xb756ede7 in gtk_widget_queue_draw () from /usr/lib/libgtk-x11-2.0.so.0
#7  0xb7398858 in gtk_cell_view_set_displayed_row ()
   from /usr/lib/libgtk-x11-2.0.so.0
#8  0xb73b8411 in gtk_combo_new () from /usr/lib/libgtk-x11-2.0.so.0
#9  0xb73b98c4 in gtk_combo_box_set_active_iter ()
   from /usr/lib/libgtk-x11-2.0.so.0
#10 0xb79cdce7 in Gtk::ComboBox::set_active (this=0x87e8234, iter=@0xb0b5ad9c)
    at libs/gtkmm2/gtk/gtkmm/combobox.cc:303
#11 0xb79ab284 in Gtk::ComboBoxText::set_active_text (this=0x87e8234, 
    text=@0xb0b5b0a4) at libs/gtkmm2/gtk/gtkmm/comboboxtext.cc:124
---Type <return> to continue, or q <return> to quit---
#12 0x083a66a1 in ARDOUR_UI::parameter_changed (this=0x87e5f78, 
    parameter_name=0xb7f3960c "slave-source")
    at gtk2_ardour/ardour_ui_options.cc:746
#13 0x08384fe9 in sigc::bound_mem_functor1<void, ARDOUR_UI, char const*>::operator() (this=0x9223894, _A_a1=@0xb0b5b1ac)
    at libs/sigc++2/sigc++/functors/mem_fun.h:1838
#14 0x08385007 in sigc::adaptor_functor<sigc::bound_mem_functor1<void, ARDOUR_UI, char const*> >::operator()<char const* const&> (this=0x9223890, 
    _A_arg1=@0xb0b5b1ac) at libs/sigc++2/sigc++/adaptors/adaptor_trait.h:84
#15 0x0838502b in sigc::internal::slot_call1<sigc::bound_mem_functor1<void, ARDOUR_UI, char const*>, void, char const*>::call_it (rep=0x9223878, 
    a_1=@0xb0b5b1ac) at libs/sigc++2/sigc++/functors/slot.h:137
#16 0x083886ec in sigc::internal::signal_emit1<void, char const*, sigc::nil>::emit (impl=0x8dfc4e0, _A_a1=@0xb0b5b1ac) at libs/sigc++2/sigc++/signal.h:646
#17 0x0838878d in sigc::signal1<void, char const*, sigc::nil>::emit (
    this=0x897ce2c, _A_a1=@0xb0b5b1ac) at libs/sigc++2/sigc++/signal.h:1694
#18 0x083887a8 in sigc::signal1<void, char const*, sigc::nil>::operator() (
    this=0x897ce2c, _A_a1=@0xb0b5b1ac) at libs/sigc++2/sigc++/signal.h:1698
#19 0xb7ee264a in ARDOUR::Configuration::set_slave_source (this=0x897ce00, 
    val=ARDOUR::None) at libs/ardour/ardour/configuration_vars.h:95
#20 0xb7f12fde in ARDOUR::Session::set_slave_source (this=0x8f1a1a0, 
    src=ARDOUR::None) at libs/ardour/session_transport.cc:983
#21 0xb7edce29 in ARDOUR::Session::process_event (this=0x8f1a1a0, ev=0x87ccf00)
---Type <return> to continue, or q <return> to quit---
    at libs/ardour/session_events.cc:400
#22 0xb7edd346 in ARDOUR::Session::merge_event (this=0x8f1a1a0, ev=0x87ccf00)
    at libs/ardour/session_events.cc:148
#23 0xb7eee9d9 in ARDOUR::Session::process_with_events (this=0x8f1a1a0, 
    nframes=1024) at libs/ardour/session_process.cc:264
#24 0xb7eef085 in ARDOUR::Session::process (this=0x8f1a1a0, nframes=1024)
    at libs/ardour/session_process.cc:61
#25 0xb7dc0ffb in ARDOUR::AudioEngine::process_callback (this=0x8967c60, 
    nframes=1024) at libs/ardour/audioengine.cc:278
#26 0xb7dc11ba in ARDOUR::AudioEngine::_process_callback (nframes=1024, 
    arg=0x8967c60) at libs/ardour/audioengine.cc:233
#27 0xb6bb10fa in jack_client_close () from /usr/lib/libjack-0.100.0.so.0
#28 0xb69d7504 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#29 0xb696b51e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 6 (Thread -1295545440 (LWP 21233)):
#0  0xb7f9e410 in ?? ()
#1  0xb2c78358 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000002 in ?? ()
#4  0x00000002 in ?? ()
#5  0xb2c78ba0 in ?? ()
#6  0x00000000 in ?? ()
---Type <return> to continue, or q <return> to quit---

Thread 5 (Thread -1287152736 (LWP 21232)):
#0  0xb7f9e410 in ?? ()
#1  0xb3479338 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000001 in ?? ()
#4  0x00000000 in ?? ()

Thread 4 (Thread -1275802720 (LWP 21223)):
#0  0xb7f9e410 in ?? ()
#1  0xb3f4c3f8 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000001 in ?? ()
#4  0x00000000 in ?? ()

Thread 3 (Thread -1247278176 (LWP 21215)):
#0  0xb7f9e410 in ?? ()
#1  0xb5a803f8 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000002 in ?? ()
#4  0x00000000 in ?? ()

Thread 2 (Thread -1238742112 (LWP 21214)):
---Type <return> to continue, or q <return> to quit---
#0  0xb7f9e410 in ?? ()
#1  0xb62a43a8 in ?? ()
#2  0xb77aa1e4 in ?? () from /usr/lib/libglib-2.0.so.0
#3  0xb62a438c in ?? ()
#4  0xb69ddbf6 in __nanosleep_nocancel ()
   from /lib/tls/i686/cmov/libpthread.so.0
#5  0xb77642f2 in g_usleep () from /usr/lib/libglib-2.0.so.0
#6  0xb6e77481 in Glib::usleep (microseconds=10000)
    at libs/glibmm2/glibmm/timer.cc:68
#7  0xb7dc07b8 in ARDOUR::AudioEngine::meter_thread (this=0x8967c60)
    at libs/ardour/audioengine.cc:387
#8  0xb7dc37f8 in sigc::bound_mem_functor0<void, ARDOUR::AudioEngine>::operator() (this=0x8967afc) at libs/sigc++2/sigc++/functors/mem_fun.h:1781
#9  0xb7dc381a in sigc::adaptor_functor<sigc::bound_mem_functor0<void, ARDOUR::AudioEngine> >::operator() (this=0x8967af8)
    at libs/sigc++2/sigc++/adaptors/adaptor_trait.h:251
#10 0xb7dc3846 in sigc::internal::slot_call0<sigc::bound_mem_functor0<void, ARDOUR::AudioEngine>, void>::call_it (rep=0x8967ae0)
    at libs/sigc++2/sigc++/functors/slot.h:103
#11 0x08354426 in sigc::slot0<void>::operator() (this=0x8967a90)
    at libs/sigc++2/sigc++/functors/slot.h:440
#12 0xb6e7d933 in call_thread_entry_slot (data=0x8967a90)
    at libs/glibmm2/glibmm/thread.cc:43
---Type <return> to continue, or q <return> to quit---
#13 0xb776238f in g_thread_create_full () from /usr/lib/libglib-2.0.so.0
#14 0xb69d7504 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#15 0xb696b51e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread -1236539728 (LWP 21202)):
#0  0xb6d63377 in sigc::internal::trackable_callback_list::remove_callback (
    this=0x9566070, data=0xa0791c8) at libs/sigc++2/sigc++/trackable.cc:114
#1  0xb6d63552 in sigc::trackable::remove_destroy_notify_callback (
    this=0x955edf0, data=0xa0791c8) at libs/sigc++2/sigc++/trackable.cc:58
#2  0x0835aef4 in sigc::internal::slot_do_unbind::operator() (this=0xbfadadf4, 
    t=0x955edf0) at libs/sigc++2/sigc++/functors/slot_base.h:166
#3  0x08530e77 in sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>::with_type<true, GainMeter>::execute_ (
    _A_type=@0x955eb48, _A_action=@0xbfadadf4)
    at libs/sigc++2/sigc++/visit_each.h:67
#4  0x08530e92 in sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>::operator()<GainMeter> (this=0xbfadadf4, 
    _A_type=@0x955eb48) at libs/sigc++2/sigc++/visit_each.h:72
#5  0x08530eac in sigc::visit_each<sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>, GainMeter> (_A_action=@0xbfadadf4, 
    _A_functor=@0x955eb48) at libs/sigc++2/sigc++/visit_each.h:113
#6  0x0853108f in sigc::visit_each<sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>, void, GainMeter, char const*> (
---Type <return> to continue, or q <return> to quit---
    _A_action=@0xbfadadf4, _A_target=@0xa0791e8)
    at libs/sigc++2/sigc++/functors/mem_fun.h:1855
#7  0x085310ad in sigc::visit_each<sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>, sigc::bound_mem_functor1<void, GainMeter, char const*> > (_A_action=@0xbfadadf4, _A_target=@0xa0791e4)
    at libs/sigc++2/sigc++/adaptors/adaptor_trait.h:264
#8  0x085310cb in sigc::visit_each<sigc::internal::limit_derived_target<sigc::trackable*, sigc::internal::slot_do_unbind>, sigc::bound_mem_functor1<void, GainMeter, char const*>, char const*> (_A_action=@0xbfadadf4, _A_target=@0xa0791e0)
    at libs/sigc++2/sigc++/adaptors/bind.h:1281
#9  0x0853110c in sigc::visit_each_type<sigc::trackable*, sigc::internal::slot_do_unbind, sigc::bind_functor<-1, sigc::bound_mem_functor1<void, GainMeter, char const*>, char const*, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil> > (_A_action=@0xbfadae1c, _A_functor=@0xa0791e0)
    at libs/sigc++2/sigc++/visit_each.h:124
#10 0x08531156 in sigc::internal::typed_slot_rep<sigc::bind_functor<-1, sigc::bound_mem_functor1<void, GainMeter, char const*>, char const*, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil, sigc::nil> >::destroy (data=0xa0791c8)
    at libs/sigc++2/sigc++/functors/slot.h:60
#11 0x083597fe in sigc::internal::slot_rep::destroy (this=0xa0791c8)
    at libs/sigc++2/sigc++/functors/slot_base.h:98
#12 0xb6d658ea in ~slot_rep (this=0xa0791c8)
    at libs/sigc++2/sigc++/functors/slot_base.h:87
---Type <return> to continue, or q <return> to quit---
#13 0xb6d65866 in ~slot_base (this=0xbfadaf10)
    at libs/sigc++2/sigc++/functors/slot_base.cc:87
#14 0x08356787 in ~slot0 (this=0xbfadaf10)
    at libs/sigc++2/sigc++/functors/slot.h:422
#15 0x0835679b in ~slot (this=0xbfadaf10)
    at libs/sigc++2/sigc++/functors/slot.h:1067
#16 0xb7bd024f in ~UIRequest (this=0xbfadaee4)
    at libs/gtkmm2ext/gtkmm2ext/gtk_ui.h:85
#17 0xb7bd052f in AbstractUI<Gtkmm2ext::UIRequest>::handle_ui_requests (
    this=0x87e5f88) at libs/pbd/pbd/abstract_ui.cc:112
#18 0xb7bc694e in Gtkmm2ext::UI::signal_pipe_callback (arg=0x87e5f78, fd=6, 
    cond=GDK_INPUT_READ) at libs/gtkmm2ext/gtk_ui.cc:334
#19 0xb72ad5ae in gdk_input_add () from /usr/lib/libgdk-x11-2.0.so.0
#20 0xb776dc8d in g_io_channel_unix_get_fd () from /usr/lib/libglib-2.0.so.0
#21 0xb7744802 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#22 0xb77477df in g_main_context_check () from /usr/lib/libglib-2.0.so.0
#23 0xb7747b89 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
#24 0xb744f574 in gtk_main () from /usr/lib/libgtk-x11-2.0.so.0
#25 0xb7966a8d in Gtk::Main::run_impl (this=0x87e5af0)
    at libs/gtkmm2/gtk/gtkmm/main.cc:503
#26 0xb796689a in Gtk::Main::run () at libs/gtkmm2/gtk/gtkmm/main.cc:450
#27 0xb7bc6ca9 in Gtkmm2ext::UI::run (this=0x87e5f78, old_receiver=@0x87c0ee4)
    at libs/gtkmm2ext/gtk_ui.cc:214
---Type <return> to continue, or q <return> to quit---
#28 0x0858c0b9 in main (argc=1, argv=0xbfadb374) at gtk2_ardour/main.cc:448
(gdb)