When I hit play on the timeline the sound effects may trigger much earlier than they appear in the timeline, especially if the video has been playing for a few seconds prior to the sound clip. If I start playback a couple seconds before the sounds then it appear synchronized.
Blender 2.69 in Ubuntu 14.04
Try enabling AV sync in Timeline > Playback:
This will tell blender to keep playback in sync with the audio, at the expense of dropping frames if the playback isn't fast enough.
By the way, 2.69 is quite an old version of blender at this point. I'd recommend using the latest version, 2.77a at the time of writing. If you wish to install blender from a repo (for automatic updates), see this question.
