lmms issue #2713, Crash on changing velocity

backtrace-full

(gdb) bt full
#0  0x000000000048e1bb in InstrumentTrack::processInEvent (this=0x20b13c0, event=..., time=..., offset=0)
    at /home/zonkmachine/builds/lmms/lmms/src/tracks/InstrumentTrack.cpp:360
        eventHandled = true
#1  0x000000000049b062 in PianoRoll::testPlayNote (this=0x1cd7320, n=0x2579a80) at /home/zonkmachine/builds/lmms/lmms/src/gui/PianoRoll.cpp:1994
        event = {m_type = MidiSystemReset, m_metaEvent = MidiNotePanning, m_channel = -1 '\377', m_data = {m_param = {108, -1}, m_bytes = "l\000\377\377", 
            m_sysExDataLen = -65428}, m_sysExData = 0x0, m_sourcePort = 0x0}
        n = 0x2579a80
        this = 0x1cd7320
#2  0x000000000049cb74 in PianoRoll::mouseMoveEvent (this=0x1cd7320, _me=0x7ffe0bcacfa0) at /home/zonkmachine/builds/lmms/lmms/src/gui/PianoRoll.cpp:2375
        n = 0x2579a80
        i = 11
        ticks_start = 66
        vol = 95 '_'
        pixel_range = 14
        ticks_end = 80
        on_note = true
        use_selection = false
        it = 0x25611a0
        edit_note = <optimized out>
        key_num = <optimized out>
        x = <optimized out>
#3  0x00000000004a5995 in PianoRoll::mousePressEvent (this=0x1cd7320, _me=0x7ffe0bcacfa0) at /home/zonkmachine/builds/lmms/lmms/src/gui/PianoRoll.cpp:1624
        pos_ticks = 73
        it = 0x25611a0
        edit_note = <optimized out>
        key_num = 80
        x = <optimized out>
#4  0x00007f774ae2138b in QWidget::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#5  0x00007f774add1e2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#6  0x00007f774add85dd in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#7  0x00007f774a6554dd in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
No symbol table info available.
#8  0x00007f774add7d93 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) ()
   from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#9  0x00007f774ae4c9eb in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#10 0x00007f774ae4c289 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#11 0x00007f774ae73b32 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#12 0x00007f77476d0e04 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#13 0x00007f77476d1048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#14 0x00007f77476d10ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
No symbol table info available.
#15 0x00007f774a6827a1 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
No symbol table info available.
---Type <return> to continue, or q <return> to quit--- 
#16 0x00007f774ae73be6 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
No symbol table info available.
#17 0x00007f774a6540af in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
No symbol table info available.
#18 0x00007f774a6543a5 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
No symbol table info available.
#19 0x00007f774a659b79 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
No symbol table info available.
#20 0x00000000004830b3 in main (argc=1, argv=<optimized out>) at /home/zonkmachine/builds/lmms/lmms/src/core/main.cpp:503
        sparam = {__sched_priority = 50}
        ret = <optimized out>
        exit_after_import = <optimized out>
        eff = <optimized out>
        pos = {static null = {<No data fields>}, static shared_null = {ref = {_q_value = 8400}, alloc = 0, size = 0, 
            data = 0x7f774a9bb93a <QString::shared_null+26>, clean = 0, simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, 
            array = {0}}, static shared_empty = {ref = {_q_value = 27}, alloc = 0, size = 0, data = 0x7f774a9bb91a <QString::shared_empty+26>, clean = 0, 
            simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0x16139c0, static codecForCStrings = 0x0}
        fullscreen = <optimized out>
        file_to_load = {static null = {<No data fields>}, static shared_null = {ref = {_q_value = 8400}, alloc = 0, size = 0, 
            data = 0x7f774a9bb93a <QString::shared_null+26>, clean = 0, simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, 
            array = {0}}, static shared_empty = {ref = {_q_value = 27}, alloc = 0, size = 0, data = 0x7f774a9bb91a <QString::shared_empty+26>, clean = 0, 
            simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0x7f774a9bb920 <QString::shared_null>, 
          static codecForCStrings = 0x0}
        file_to_save = {static null = {<No data fields>}, static shared_null = {ref = {_q_value = 8400}, alloc = 0, size = 0, 
            data = 0x7f774a9bb93a <QString::shared_null+26>, clean = 0, simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, 
            array = {0}}, static shared_empty = {ref = {_q_value = 27}, alloc = 0, size = 0, data = 0x7f774a9bb91a <QString::shared_empty+26>, clean = 0, 
            simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0x7f774a9bb920 <QString::shared_null>, 
          static codecForCStrings = 0x0}
        app = 0x159fe20
        os = {samplerate = 44100, vbr = false, bitrate = 160, depth = ProjectRenderer::Depth_16Bit}
        core_only = <optimized out>
        file_to_import = {static null = {<No data fields>}, static shared_null = {ref = {_q_value = 8400}, alloc = 0, size = 0, 
            data = 0x7f774a9bb93a <QString::shared_null+26>, clean = 0, simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, 
            array = {0}}, static shared_empty = {ref = {_q_value = 27}, alloc = 0, size = 0, data = 0x7f774a9bb91a <QString::shared_empty+26>, clean = 0, 
            simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0x7f774a9bb920 <QString::shared_null>, 
          static codecForCStrings = 0x0}
        render_out = {static null = {<No data fields>}, static shared_null = {ref = {_q_value = 8400}, alloc = 0, size = 0, 
            data = 0x7f774a9bb93a <QString::shared_null+26>, clean = 0, simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, 
            array = {0}}, static shared_empty = {ref = {_q_value = 27}, alloc = 0, size = 0, data = 0x7f774a9bb91a <QString::shared_empty+26>, clean = 0, 
            simpletext = 0, righttoleft = 0, asciiCache = 0, capacity = 0, reserved = 0, array = {0}}, d = 0x7f774a9bb920 <QString::shared_null>, 
          static codecForCStrings = 0x0}
        qs = {interpolation = Mixer::qualitySettings::Interpolation_SincFastest, oversampling = Mixer::qualitySettings::Oversampling_2x}
(gdb)