Problems with mkv media files.

[Alex]

Thanks rokytnji, i;ll try all those out and report on my efforts. meanwhile, I obtained another copy of the same movie but this time an .mp4 file of only 800Mb. It played fine on Kaffeine, but something strange has happened to my VLC player: it shows a display of many superimposed 'ghosts of other scenes on top of the main one: