Yes. There are two possibilities:

• Activate the faststart-function (Attention: consider the FAQ: "What is the faststart-setting in the backend good for?")
• Install psstream: http://codeblog.palos.ro/2008/11/13/pseudo-streaming-mp4h264-video-from-...
  This extension allows the immediate playback of mp4-files.
  As psstream is a third-party product, we can not provide support for it.

The faststart-application of ffmpeg allows to play HD-video, befor they are downloaded completely.

Depending on the server-systemit can be, that the conversion is failing and does not produce images for the video.In this case the faststart-function must be deactivated.

• The conversion of HD-video usually takes longer than with lower resolution video. Many servers can only convert 10 frames per second., why the encoding of on minute of video material can take 2-3 minutes.
• Originated in the big display of HD-video also the file size rises: a video with a resolution of 1280x720 (720p) accordingly needs about 8 MB of disc space per minunte
• Additional codecs have to be installed: ACC for audio and x264 for video

The quality of uploaded video often is too high, which can be caused by an incorrect version setting in the admin area, or because the videos were uploaded as too high compressed FLV-file.

Resulting problems include that the computing power of the computer playing the videos back is too low (this can be checked by watching CPU usage in task manager). Dual-core systems with a minimum of 2 GBs of RAM and higher are recommended.

The problem can also be contributed to by low data transfer rates with the internet connection