My suspicion is you have shut off REAL-TIME PREVIEW.
Your AUDIO icon underneath the preview window has a SLASH through it. This indicates you have muted the audio causing it to go into NON REAL-TIME mode. This function serves to lessen the strain on your computer when editing making the preview a little smoother because it's ignoring the audio portion of your timelines.
Just to the left of the speaker icon, under the preview window, there is a dialogue box, click on that and change the setting to REAL-TIME. This depends of course on if this is indeed your issue.
This message was edited 1 time. Last update was at Feb 01. 2017 08:57
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