QT change QSystemTrayIcon at runtime - qt

Question

I'm trying to change the QSystemTrayIcon at various points in my application, example:
void MainWindow::goOnline() {
isOnlineFlag = true;
QIcon xmediaIcon("://notificationLogo.png");
sti->setIcon(xmediaIcon);
}
void MainWindow::goOffline(bool manual) {
isOnlineFlag = false;
QIcon xmediaIcon("://notificationLogoOffline.png");
sti->setIcon(xmediaIcon);
}
But for some reason the application crashes at times.
Crash log:
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0 QtGui 0x0000000101813171 QIcon::operator=(QIcon const&) + 33
1 QtWidgets 0x000000010207a2d6 QSystemTrayIcon::setIcon(QIcon const&) + 22
2 com.yourcompany.app 0x000000010002b089 MainWindow::goOffline(bool) + 617
3 com.yourcompany.app 0x00000001000bb736 MainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) + 19382
4 QtCore 0x00000001013edda6 QMetaObject::activate(QObject*, int, int, void**) + 2550
5 QtCore 0x00000001013e6c93 QObject::event(QEvent*) + 51
6 QtWidgets 0x0000000101d55f2c QApplicationPrivate::notify_helper(QObject*, QEvent*) + 300
7 QtWidgets 0x0000000101d58a1d QApplication::notify(QObject*, QEvent*) + 6157
8 QtCore 0x00000001013bd0b2 QCoreApplication::notifyInternal(QObject*, QEvent*) + 114
9 QtCore 0x000000010140e746 QTimerInfoList::activateTimers() + 982
10 libqcocoa.dylib 0x0000000104e58fc5 QCocoaEventDispatcherPrivate::activateTimersSourceCallback(void*) + 21
11 com.apple.CoreFoundation 0x00007fff9038c731 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
12 com.apple.CoreFoundation 0x00007fff9037dea2 __CFRunLoopDoSources0 + 242
13 com.apple.CoreFoundation 0x00007fff9037d62f __CFRunLoopRun + 831
14 com.apple.CoreFoundation 0x00007fff9037d0b5 CFRunLoopRunSpecific + 309
15 com.apple.HIToolbox 0x00007fff86261a0d RunCurrentEventLoopInMode + 226
16 com.apple.HIToolbox 0x00007fff862617b7 ReceiveNextEventCommon + 479
17 com.apple.HIToolbox 0x00007fff862615bc _BlockUntilNextEventMatchingListInModeWithFilter + 65
18 com.apple.AppKit 0x00007fff837193de _DPSNextEvent + 1434
19 com.apple.AppKit 0x00007fff83718a2b -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 122
20 com.apple.AppKit 0x00007fff8370cb2c -[NSApplication run] + 553
21 libqcocoa.dylib 0x0000000104e59d44 QCocoaEventDispatcher::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 2404
22 QtCore 0x00000001013ba64d QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 397
23 QtCore 0x00000001013bd652 QCoreApplication::exec() + 354
24 com.yourcompany.app 0x0000000100007906 main + 1558
25 com.yourcompany.app 0x0000000100006584 start + 52
Any ideas what the problem could be?