Lets create another thread for this specific problem.... Because it hit me randomly on file load :/ cinelerra git log top: commit fb3e53778e49a406768506de9bf8edfd3d4c36e6 (HEAD -> master) Author: Good Guy <[email protected]> Date: Sat Apr 25 19:41:57 2020 -0600 split resource_thread update into separate audio/video threads, boxblur layout tweaks ffmpeg git log top: commit 38737b3d4e03e2a089083e38cd1fd6f9b4c3ddfd (HEAD -> master, origin/master, origin/HEAD) Author: Steven Liu <[email protected]> Date: Fri Jun 12 14:30:02 2020 +0800 mailmap: add entry for myself Configure line: LDFLAGS=-L/usr/X11R7/lib setarch i686 ./configure --prefix=/usr --with-git-ffmpeg=https://git.ffmpeg.org/ffmpeg.git --sysconfdir=/etc --localstatedir=/var --libdir=/usr/lib --with-ladspa-build --with-opus --with-nv --enable-opus --with-jobs=4 --with-booby --build=i486-slackware-linux build_alias=i486-slackware-linux CC="ccache gcc" CFLAGS="-O3 -march=i686 -mtune=i686 -D__STDC_CONSTANT_MACROS" LDFLAGS="-L/usr/X11R7/lib -ldl -L/usr/lib" CXX=clang++ CXXFLAGS="-O3 -march=i686 -mtune=i686 -D__STDC_CONSTANT_MACROS" --no-create --no-recursion --with-commercial yeah, quite aggressive, I know .... Action: 1) open program 1.1) Set load strategy to 'Create resources only' 2) try to load my KARA... .mkv file ('O' then navigate to folder where file is and the doubleclick on it - only resource should appear, timeline still in default state - 3 tracks, one for video, 2 for audio) 3) drag file from Resources on timeline. If it loads correctly - undo loading, and try again. Eventually it will hit this assert. terminal output guest@slax:/dev/shm/tmp/cinelerra-goodguy-20200607/cinelerra-5.1/bin$ ./cin Cinelerra Infinity - built: Jun 13 2020 04:36:31 git://git.cinelerra-gg.org/goodguy/cinelerra.git (c) 2006-2019 Heroine Virtual Ltd. by Adam Williams 2007-2020 mods for Cinelerra-GG by W.P.Morrow aka goodguy Cinelerra is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. There is absolutely no warranty for Cinelerra. RenderFarmClient::main_loop: client started FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv FFMPEG::open_decoder: some stream times estimated: /home/guest/New_hdd/KARA (Quantic Dream) [HD]-wxVyeSfE6p8.mkv Assertion fctx->async_lock failed at libavcodec/pthread_frame.c:155 Аварийный останов guest@slax:/dev/shm/tmp/cinelerra-goodguy-20200607/cinelerra-5.1/bin$ Thing is, I was unable to make it assert with ffmpeg.patch provided :/ (on very same sw and hw) may be patch slows down all those threading operation enough for assertion to be avoided ?