I turned on my mac and realised there was no sound coming from it. I tried clicking the turn up volume button but the speaker symbol is dark and the is a cross underneath the sound bar. When I go into system preferences for sound it says it can't find any input and output devices. this happened overnight its like a switch has been switched somehow. Do you know how to fix this?
iMac, OS X Mavericks (10.9.5)
Go step by step and test
1.Plug in and remove the headphone.
If you see red light in the headphone port, plug the headphone
in and out of the port 5 or 6 times to flip the microswitch inside.
Sound output may be stuck in the digital mode.
2. Reset PRAM. http://support.apple.com/kb/PH14222
3. Reset SMC. http://support.apple.com/kb/HT3964
Choose the appropriate method.
4. Applications > Utilities > Audio MIDI Setup
Audio Devices window
Side Bar
Click the Built-in Output.
Make sure that no box is checked under “Mute”.
5. System Preferences > Sound> Sound Effects
Play sound effects through:
Select "Internal speakers" and then back to "Selected sound output device".
6. Launch iTunes and play a song through headphone and adjust the volume
in mini player.
Restart.
why is there no sound output devices found?
