As per earlier post, ################### clip ###################### ffplay -i info for the ORIGINAL file from camera (ie that is imported to Openshot): ffplay -i ./Pictures/100CASIO/CIMG1113.AVI ffplay version 0.7.6-4:0.7.6-0ubuntu0.11.10.1, Copyright (c) 2003-2011 the Libav developers built on Jun 12 2012 16:28:10 with gcc 4.6.1 : : Input #0, avi, from './Pictures/100CASIO/CIMG1113.AVI': Metadata: creation_time : 2012-10-07/ 08:40 encoder : CASIO EX-Z60 Duration: 00:00:45.77, start: 0.000000, bitrate: 2282 kb/s Stream #0.0: Video: mjpeg, yuvj420p, 320x240, 14.99 tbr, 14.99 tbn, 14.99 tbc Stream #0.1: Audio: adpcm_ima_wav, 11025 Hz, 1 channels, s16, 44 kb/s ############### end clip ####################### Thanks for the reference to the ppa for latest MLT version; have installed that, see below for detail. IF Openshot is started in the back-ground with &, behaviour is as described earlier. Tried starting Openshot as the foreground process, FOR ONE OUT OF 2 TRIALS then only the 'video seek' controls are frozen; was able to minimize the Openshot window, bring a terminal window to the foreground, and check process state. Need to repeat this trial a few times (takes time), trying to ensure that exactly the same set of key press / commands / clicks etc is used each time to eliminate variation in them as a cause. Here are last few lines printed by Openshot (started as foreground, the 1 time it did not completely freeze) as I re-sized the clip and tried to preview, then escaped the 'lock-up': (NOTE, I have not defined a project for these trials). state saved on_btnZoomIn_clicked on_btnZoomIn_clicked set_preview_mode set_view_mode project state modified state saved set_preview_mode set_view_mode project state modified state saved set_preview_mode set_view_mode project state modified state saved set_preview_mode set_view_mode project state modified state saved on_tlbPlay_clicked called with self.GtkToolButton ^Z [1]+ Stopped openshot ./Pictures/100CASIO/CIMG1113.AVI charlie@fiona-ubuLenovo-3000-G530:~$ bg 1 [1]+ openshot ./Pictures/100CASIO/CIMG1113.AVI & charlie@fiona-ubuLenovo-3000-G530:~$ ps -elF |grep 'openshot' 0 S charlie 1942 1 1 80 0 - 180475 poll_s 201244 0 08:57 ? 00:05:47 /usr/lib/firefox/firefox https://answers.launchpad.net/openshot/+faq/983 0 S charlie 6256 2023 41 80 0 - 93888 poll_s 128760 0 15:16 pts/0 00:01:28 /usr/bin/python /usr/bin/openshot ./Pictures/100CASIO/CIMG1113.AVI 0 S charlie 6287 2023 0 80 0 - 1055 pipe_w 772 0 15:19 pts/0 00:00:00 grep --color=auto openshot charlie@fiona-ubuLenovo-3000-G530:~$ kill -9 6256 charlie@fiona-ubuLenovo-3000-G530:~$ [1]+ Killed openshot ./Pictures/100CASIO/CIMG1113.AVI ################################################################################ What you do NOT see on the console log above is the 'pause' button legend that is 'stuck' in the middle of the screen: see attached screenshot. Dunno if it is relevant, but extra/changed message at openshot start-up after upgrading MLT: charlie@fiona-ubuLenovo-3000-G530:~$ ------------------------- ERROR 1 ------------------------------ Failed to import 'from openshot import main' Error Message: cannot import name main ---------------------------------------------------------------- -------------------------------- OpenShot (version 1.4.3) -------------------------------- Process no longer exists: 5705. Creating new pid lock file. Adding files to the watch queue: /home/charlie/Pictures/100CASIO/CIMG1113.AVI No LADSPA plugins were found! Check your LADSPA_PATH environment variable. Detecting formats, codecs, and filters... --- #################################################