Application: kmix (4.1)
KDE Platform Version: 4.8.4 (4.8.4)
Qt Version: 4.8.1
Operating System: Linux 3.2.0-26-generic x86_64
Distribution: KXStudio 12.04

-- Information about the crash:
KMix always craches when I turn on my synthesizer (Yamaha PSR-1500) that is connected via USB. ALSA indentifies it as an external sound card with MIDI support.
Restarting KMix works without any problems.

The crash can be reproduced every time.

-- Backtrace:
Application: KMix (kmix), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f518f5177c0 (LWP 4647))]

Thread 3 (Thread 0x7f516d898700 (LWP 4648)):
#0  0x00007f518ede00bd in read () at ../sysdeps/unix/syscall-template.S:82
#1  0x00007f5180b090bc in ?? () from /usr/lib/nvidia-current/libGL.so.1
#2  0x00007f517e37cb27 in ?? () from /usr/lib/nvidia-current/tls/libnvidia-tls.so.295.40
#3  0x00007f5184c2a8cf in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f5184befba4 in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f5184beffd6 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007f5184bf0164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#7  0x00007f518bb6c426 in QEventDispatcherGlib::processEvents (this=0x7f51680008e0, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#8  0x00007f518bb3bc82 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#9  0x00007f518bb3bed7 in QEventLoop::exec (this=0x7f516d897cd0, flags=...) at kernel/qeventloop.cpp:204
#10 0x00007f518ba3afa7 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:501
#11 0x00007f518bb1b9ff in QInotifyFileSystemWatcherEngine::run (this=0x1709720) at io/qfilesystemwatcher_inotify.cpp:248
#12 0x00007f518ba3dfcb in QThreadPrivate::start (arg=0x1709720) at thread/qthread_unix.cpp:298
#13 0x00007f5180b0ab74 in ?? () from /usr/lib/nvidia-current/libGL.so.1
#14 0x00007f5185756e9a in start_thread (arg=0x7f516d898700) at pthread_create.c:308
#15 0x00007f518eded4bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#16 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f516ce8b700 (LWP 4649)):
#0  0x00007f518ede1b03 in __GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007f5184bf0036 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f5184bf0164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f518bb6c426 in QEventDispatcherGlib::processEvents (this=0x7f51600008e0, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#4  0x00007f518bb3bc82 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#5  0x00007f518bb3bed7 in QEventLoop::exec (this=0x7f516ce8acd0, flags=...) at kernel/qeventloop.cpp:204
#6  0x00007f518ba3afa7 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:501
#7  0x00007f518bb1b9ff in QInotifyFileSystemWatcherEngine::run (this=0x1755760) at io/qfilesystemwatcher_inotify.cpp:248
#8  0x00007f518ba3dfcb in QThreadPrivate::start (arg=0x1755760) at thread/qthread_unix.cpp:298
#9  0x00007f5180b0ab74 in ?? () from /usr/lib/nvidia-current/libGL.so.1
#10 0x00007f5185756e9a in start_thread (arg=0x7f516ce8b700) at pthread_create.c:308
#11 0x00007f518eded4bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#12 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f518f5177c0 (LWP 4647)):
[KCrash Handler]
#6  0x00007f518f101e7e in KMixWindow::recreateGUI (this=0x14818e0, saveConfig=<optimized out>, mixerId=..., forceNewTab=true) at ../../kmix/apps/kmix.cpp:663
#7  0x00007f518f10301c in KMixWindow::plugged (this=0x14818e0, driverName=<optimized out>, udi=..., dev=...) at ../../kmix/apps/kmix.cpp:855
#8  0x00007f518f103f9c in qt_static_metacall (_a=<optimized out>, _id=<optimized out>, _o=0x14818e0, _c=<optimized out>) at ./kmix.moc:131
#9  KMixWindow::qt_static_metacall (_o=0x14818e0, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at ./kmix.moc:103
#10 0x00007f518bb51281 in QMetaObject::activate (sender=0x17207a0, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffe10f82b0) at kernel/qobject.cpp:3547
#11 0x00007f518f128449 in KMixDeviceManager::plugged (this=<optimized out>, _t1=0x7f518f134ea4 "ALSA", _t2=..., _t3=...) at ./kmixdevicemanager.moc:109
#12 0x00007f518f128a6d in KMixDeviceManager::pluggedSlot (this=0x17207a0, udi=...) at ../../kmix/core/kmixdevicemanager.cpp:134
#13 0x00007f518bb51281 in QMetaObject::activate (sender=0x17207c0, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffe10f85a0) at kernel/qobject.cpp:3547
#14 0x00007f518e7e1532 in Solid::DeviceNotifier::deviceAdded (this=<optimized out>, _t1=...) at ./devicenotifier.moc:101
#15 0x00007f518e7e274c in Solid::DeviceManagerPrivate::_k_deviceAdded (this=0x17207c0, udi=...) at ../../../solid/solid/devicemanager.cpp:189
#16 0x00007f518bb51281 in QMetaObject::activate (sender=0x174d390, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffe10f8790) at kernel/qobject.cpp:3547
#17 0x00007f518e7f7662 in Solid::Ifaces::DeviceManager::deviceAdded (this=<optimized out>, _t1=...) at ./ifaces/devicemanager.moc:101
#18 0x00007f518e80e274 in Solid::Backends::UDev::UDevManager::slotDeviceAdded (this=0x174d390, device=...) at ../../../solid/solid/backends/udev/udevmanager.cpp:201
#19 0x00007f518bb51281 in QMetaObject::activate (sender=0x174d680, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffe10f8920) at kernel/qobject.cpp:3547
#20 0x00007f518e8178d2 in UdevQt::Client::deviceAdded (this=<optimized out>, _t1=...) at ./udevqt.moc:146
#21 0x00007f518e817a30 in UdevQt::ClientPrivate::_uq_monitorReadyRead (this=0x174d730, fd=<optimized out>) at ../../../solid/solid/backends/shared/udevqtclient.cpp:105
#22 0x00007f518bb51281 in QMetaObject::activate (sender=0x174d940, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fffe10f8ab0) at kernel/qobject.cpp:3547
#23 0x00007f518bb9e2fe in QSocketNotifier::activated (this=<optimized out>, _t1=14) at .moc/release-shared/moc_qsocketnotifier.cpp:103
#24 0x00007f518bb5a60b in QSocketNotifier::event (this=0x174d940, e=0x7fffe10f9120) at kernel/qsocketnotifier.cpp:317
#25 0x00007f518c7b4894 in notify_helper (e=0x7fffe10f9120, receiver=0x174d940, this=0x1374840) at kernel/qapplication.cpp:4559
#26 QApplicationPrivate::notify_helper (this=0x1374840, receiver=0x174d940, e=0x7fffe10f9120) at kernel/qapplication.cpp:4531
#27 0x00007f518c7b9713 in QApplication::notify (this=0x13213a0, receiver=0x174d940, e=0x7fffe10f9120) at kernel/qapplication.cpp:4420
#28 0x00007f518e3709e6 in KApplication::notify (this=0x13213a0, receiver=0x174d940, event=0x7fffe10f9120) at ../../kdeui/kernel/kapplication.cpp:311
#29 0x00007f518bb3ce9c in QCoreApplication::notifyInternal (this=0x13213a0, receiver=0x174d940, event=0x7fffe10f9120) at kernel/qcoreapplication.cpp:876
#30 0x00007f518bb6ba97 in sendEvent (event=0x7fffe10f9120, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#31 socketNotifierSourceDispatch (source=0x1374720) at kernel/qeventdispatcher_glib.cpp:110
#32 0x00007f5184befd53 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#33 0x00007f5184bf00a0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#34 0x00007f5184bf0164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#35 0x00007f518bb6c426 in QEventDispatcherGlib::processEvents (this=0x12bbad0, flags=...) at kernel/qeventdispatcher_glib.cpp:426
#36 0x00007f518c85cd5e in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#37 0x00007f518bb3bc82 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#38 0x00007f518bb3bed7 in QEventLoop::exec (this=0x7fffe10f9330, flags=...) at kernel/qeventloop.cpp:204
#39 0x00007f518bb40f67 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1148
#40 0x00007f518f0fc672 in kdemain (argc=5, argv=0x7fffe10f98b8) at ../../kmix/apps/main.cpp:76
#41 0x00007f518ed1c76d in __libc_start_main (main=0x400630 <main(int, char**)>, argc=5, ubp_av=0x7fffe10f98b8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffe10f98a8) at libc-start.c:226
#42 0x0000000000400661 in _start ()

Reported using DrKonqi