I have a brand new Dell Inspiron 15 3000 series that whenever I wake it up from sleep, the sound stops working. Reboot, sound is fine. Sleep/resume, sound stops working. If I go to "Sound" in the control panel while mp3s are playing, I can see the meter moving. There just isn't any sound coming out of my laptop speakers.

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Realtek audio, latest drivers. Volume has not been muted due to use of FN keys. System tray audio mixer has the same volume level that worked well before I put the laptop to sleep.