Same probleme here on a fresh install of Hardy.

output :

Debug: Core::startMplayer: command: '/usr/bin/mplayer -noquiet -nofs -sub-fuzziness 1 -identify -slave -vo xv -ao pulse -zoom -nokeepaspect -framedrop -dr -input conf=/usr/share/smplayer/input.conf -stop-xscreensaver -wid 50331662 -colorkey 0x020202 -monitoraspect 1.6 -subfont-autoscale 1 -subfont-text-scale 5 -subcp ISO-8859-1 -subpos 100 -contrast 0 -brightness 0 -hue 0 -saturation 0 -cache 1000 -osdlevel 0 -idx -vf-add screenshot -channels 2 -af scaletempo -softvol -softvol-max 110 /home/nevada/Bureau/Mamoth/Clips/Birds.mov'
Debug: MplayerLayer::playingStarted
Debug: BaseGui::calculateDiff: diff_size: 0, 0
Debug: BaseGui::calculateDiff: diff_size set to: 0, 125
Debug: MplayerProcess::init_rx
Debug: Playlist::setModified: 0
Debug: Playlist::addFiles
Debug: Playlist::addItem: '/home/nevada/Bureau/Mamoth/Clips/Birds.mov'
Debug: name: 'Birds.mov'
Debug:  * latest_dir: ''
Debug: MplayerProcess::parseLine: 'MPlayer 1.0rc2-4.2.3 (C) 2000-2007 MPlayer Team'
Debug: MplayerVersion::mplayerVersion: MPlayer version found: 1.0rc2
Debug: MplayerProcess::parseLine: MPlayer SVN: 24722
Debug: MplayerProcess::parseLine: 'CPU: Intel(R) Celeron(R) CPU          440  @ 2.00GHz (Family: 6, Model: 22, Stepping: 1)'
Debug: MplayerProcess::parseLine: 'CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1'
Debug: MplayerProcess::parseLine: 'Compiled with runtime CPU detection.'
Debug: MplayerProcess::parseLine: 'mplayer: could not connect to socket'
Debug: MplayerProcess::parseLine: 'mplayer: No such file or directory'
Debug: MplayerProcess::parseLine: 'Failed to open LIRC support. You will not be able to use your remote control.'
Debug: MplayerProcess::parseLine: ''
Debug: MplayerProcess::parseLine: 'Playing /home/nevada/Bureau/Mamoth/Clips/Birds.mov.'
Debug: MplayerProcess::parseLine: ''
Debug: MplayerProcess::parseLine: 'Cache fill:  0.00% (0 bytes)   '
Debug: Core::displayMessage
Debug: MplayerProcess::parseLine: 'ISO: File Type Major Brand: Original QuickTime'
Debug: MplayerProcess::parseLine: 'Quicktime/MOV file format detected.'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_ID=0'
Debug: MplayerProcess::parseLine: ID_AUDIO_ID: 0
Debug: MplayerProcess::parseLine: '[mov] Audio stream found, -aid 0'
Debug: MplayerProcess::parseLine: 'ID_VIDEO_ID=1'
Debug: MplayerProcess::parseLine: '[mov] Video stream found, -vid 1'
Debug: MplayerProcess::parseLine: 'VIDEO:  [SVQ3]  300x240  24bpp  25.000 fps    0.0 kbps ( 0.0 kbyte/s)'
Debug: MplayerProcess::parseLine: 'ID_FILENAME=/home/nevada/Bureau/Mamoth/Clips/Birds.mov'
Debug: MplayerProcess::parseLine: 'ID_DEMUXER=mov'
Debug: MplayerProcess::parseLine: 'ID_VIDEO_FORMAT=SVQ3'
Debug: MplayerProcess::parseLine: 'ID_VIDEO_BITRATE=0'
Debug: MplayerProcess::parseLine: 'ID_VIDEO_WIDTH=300'
Debug: MplayerProcess::parseLine: md.video_width set to 300
Debug: MplayerProcess::parseLine: 'ID_VIDEO_HEIGHT=240'
Debug: MplayerProcess::parseLine: md.video_height set to 240
Debug: MplayerProcess::parseLine: 'ID_VIDEO_FPS=25.000'
Debug: MplayerProcess::parseLine: 'ID_VIDEO_ASPECT=0.0000'
Debug: MplayerProcess::parseLine: md.video_aspect set to 1.250000
Debug: MplayerProcess::parseLine: 'ID_AUDIO_FORMAT=mp4a'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_BITRATE=128000'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_RATE=44100'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_NCH=2'
Debug: MplayerProcess::parseLine: 'ID_LENGTH=184.12'
Debug: MplayerProcess::parseLine: md.duration set to 184.120000
Debug: MplayerProcess::parseLine: 'xscreensaver_disable: Could not find XScreenSaver window.'
Debug: MplayerProcess::parseLine: 'GNOME screensaver disabled'
Debug: MplayerProcess::parseLine: 'Opening video filter: [screenshot]'
Debug: MplayerProcess::parseLine: '=========================================================================='
Debug: MplayerProcess::parseLine: 'Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family'
Debug: MplayerProcess::parseLine: 'Selected video codec: [ffsvq3] vfm: ffmpeg (FFmpeg Sorenson Video v3 (SVQ3))'
Debug: MplayerProcess::parseLine: '=========================================================================='
Debug: MplayerProcess::parseLine: 'ID_VIDEO_CODEC=ffsvq3'
Debug: MplayerProcess::parseLine: '=========================================================================='
Debug: MplayerProcess::parseLine: 'Forced audio codec: mad'
Debug: MplayerProcess::parseLine: 'Opening audio decoder: [faad] AAC (MPEG2/4 Advanced Audio Coding)'
Debug: MplayerProcess::parseLine: 'AUDIO: 44100 Hz, 2 ch, s16le, 128.0 kbit/9.07% (ratio: 16000->176400)'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_BITRATE=128000'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_RATE=44100'
Debug: MplayerProcess::parseLine: 'ID_AUDIO_NCH=2'
Debug: MplayerProcess::parseLine: 'Selected audio codec: [faad] afm: faad (FAAD AAC (MPEG-2/MPEG-4 Audio) decoder)'
Debug: MplayerProcess::parseLine: '=========================================================================='
Debug: MplayerProcess::parseLine: 'Couldn't find audio filter 'scaletempo''
Debug: MplayerProcess::parseLine: '[libaf] Couldn't create or open audio filter 'scaletempo''
Debug: MplayerProcess::parseLine: 'Error at audio filter chain pre-init!'
Debug: MplayerProcess::parseLine: ''
Debug: MplayerProcess::parseLine: 'Exiting... (Fatal error)'
Debug: MyProcess::procFinished
Debug: MyProcess::procFinished: Bytes available: 0
Debug: MplayerProcess::processFinished
Debug: Core::processFinished
Debug: Core::processFinished: we_are_restarting: 0
Debug: Core::processFinished: play has finished!
Debug:  exit_status: 0
Debug: MplayerLayer::playingStopped