No audio playback in VSE but rendered file has audio I can not get audio to play out of my speakers whilst using Blender 2.77a in the Video Sequence Editor. However when I rendered out a file (mp4) it contains the audio and can be played back on VLC. Plus when I use mediainfo it reports the file as having audio. I need to be able to hear the audio in the VSE whilst I'm editing the images.

When selecting Draw Waveform in the Sound menu a waveform is drawn on the clip that matches the audio (highs and lows are in the right place). Below is a screen shot of my Blender User Preferences.



I have tried all the Audio Device options under Sound but none of them have worked. Each time I changed the Audio Device options I restarted the computer.

Below is a screen shot of my Output and Encoding options from the Render menu.



From some of the threads that I read some people were pointing towards sound card configurations. I am fairly new with using Blender so I am not aware of more advanced configuration options. I have spend one whole day trying to solve this problem by following similar post found via Google but have had no luck. If you need more information please ask.

Thanks very much.

System information: 


Ubuntu 14.04 LTS 
Blender 2.77a
To enable the sound in my Video Sequencing Editor, I had to change the system setting for audio device from OpenAL to SDL. Doing this seemed to jar loose the sound so that it would play.  I was even able to change the setting back to OpenAL and the sound continued to be enabled.  Strange, huh?  The sound works fine now.

Go to File> User Preferences> System> Sound: Audio Device.