Hi Joe, On 26/04/2020 14.01, Joe D wrote: > Attached a valgrind log
>> root@ubuntu-srv-10:/Applications/gnuradio/build/gr-qtgui/python/qtgui# >> valgrind -v ctest -V -R qa_qtgui You can't run this test under valgrind like this. You need to open ./build/gr-qtgui/python/qtgui/qa_qtgui_test.sh and on the last line add valgrind in front of python3. Something like: valgrind /usr/bin/python3 -B /Applications/gnuradio/gr-qtgui/python/qtgui/qa_qtgui.py Similarly you can run it under gdb in order to get a full backtrace of this segfault. Regards, Vasil