Playback sound cutting out

Please ignore this post: After posting it, I discovered the problem is with my computer, instead of Audacity. For some unknown reason, Audacity has started cutting out playback sound randomly in recorded files. Audio is still registering on the VU meter, but I cannot hear it. I can close the program and restart it to hear the audio, but it continues to cut out randomly. What has happened to make this occur, and how can I correct it