The crash occurs during login. If I disable session management or add korgac to excluded applications, the crash does not occur. Otherwise, it happens during every login.

Reproducible: Always

Steps to Reproduce:
1. Enable session management (SystemSettings->Startup and Shutdown->Desktop Session->On Login->Restore previous session)
2. Make sure that korgac is not in the list of excluded apps
3. Logout->Login

Actual Results:  
korgac throws a segmentation violation (SEGV) and dumps core.

Expected Results:  
No crash

korgac v16.08.2

-- Backtrace:
Application: korgac (korgac), signal: Segmentation fault
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[Current thread is 1 (Thread 0xa945a7c0 (LWP 919))]

Thread 5 (Thread 0xa3c4db40 (LWP 1099)):
#0  0xb7716d41 in __kernel_vsyscall ()
#1  0xb3750c8b in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#2  0xa77a7a4a in ?? () from /usr/lib/xorg/modules/dri/swrast_dri.so
#3  0xb374b301 in start_thread () from /usr/lib/libpthread.so.0
#4  0xb4f720ae in clone () from /usr/lib/libc.so.6

Thread 4 (Thread 0xa444eb40 (LWP 1098)):
#0  0xb7716d41 in __kernel_vsyscall ()
#1  0xb3750c8b in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#2  0xa77a7a4a in ?? () from /usr/lib/xorg/modules/dri/swrast_dri.so
#3  0xb374b301 in start_thread () from /usr/lib/libpthread.so.0
#4  0xb4f720ae in clone () from /usr/lib/libc.so.6

Thread 3 (Thread 0xa8667b40 (LWP 1087)):
[KCrash Handler]
#7  0xb5475e45 in QObject::disconnect(QObject const*, char const*, QObject const*, char const*) () from /usr/lib/libQt5Core.so.5
#8  0xb56e685d in ?? () from /usr/lib/libQt5DBus.so.5
#9  0xb56d3195 in ?? () from /usr/lib/libQt5DBus.so.5
#10 0xb52736fa in ?? () from /usr/lib/libQt5Core.so.5
#11 0xb374b301 in start_thread () from /usr/lib/libpthread.so.0
#12 0xb4f720ae in clone () from /usr/lib/libc.so.6

Thread 2 (Thread 0xa90e8b40 (LWP 1061)):
#0  0xb7716d41 in __kernel_vsyscall ()
#1  0xb4f6815f in poll () from /usr/lib/libc.so.6
#2  0xb387094d in ?? () from /usr/lib/libxcb.so.1
#3  0xb3872cc3 in xcb_wait_for_event () from /usr/lib/libxcb.so.1
#4  0xa91761e3 in ?? () from /usr/lib/libQt5XcbQpa.so.5
#5  0xb52736fa in ?? () from /usr/lib/libQt5Core.so.5
#6  0xb374b301 in start_thread () from /usr/lib/libpthread.so.0
#7  0xb4f720ae in clone () from /usr/lib/libc.so.6

Thread 1 (Thread 0xa945a7c0 (LWP 919)):
#0  0xb7716d41 in __kernel_vsyscall ()
#1  0xb3750c8b in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#2  0xb52745a3 in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/libQt5Core.so.5
#3  0xb5273242 in QThread::wait(unsigned long) () from /usr/lib/libQt5Core.so.5
#4  0xb56d2ebf in ?? () from /usr/lib/libQt5DBus.so.5
#5  0xb56d2f78 in ?? () from /usr/lib/libQt5DBus.so.5
#6  0xb4eb78cb in __run_exit_handlers () from /usr/lib/libc.so.6
#7  0xb4eb7931 in exit () from /usr/lib/libc.so.6
#8  0xb6757937 in KDBusService::KDBusService(QFlags<KDBusService::StartupOption>, QObject*) () from /usr/lib/libKF5DBusAddons.so.5
#9  0x0805572e in ?? ()
#10 0xb4ea1196 in __libc_start_main () from /usr/lib/libc.so.6
#11 0x080559d3 in _start ()


This can be worked around by adding korgac to the list of "Applications to be excluded from sessions" via SystemSettings->Startup and Shutdown->Desktop Session->On Login.