No audio, and no "Internal Speakers" in SystemPrefs>Sound>Output
I am really stumped by this problem, and I'm really hoping you guys can help as I'm pretty sure it's a hardware issue...
Basically, I get no audio from my MacBook Pro Retina 13" Late 2013 A1502 16Gb 2.6GHz - everything else works beautifully as ever with this machine (incl USB & power) apart from the sound.
It has *not* experienced any water damage or drops, but I'm pretty sure this problem started when I plugged in my external power speakers' amp to the headphone jack... just like I did everyday before that, but for some reason this time I didn't get any sound output and the volume feedback was delayed when I tried to turn the volume up/down.
- Built-in speakers don't make any sounds.
- No sound coming from output jack (headphones or external speakers).
- I see the volume no-access icon (circle with diagonal line through it) when trying to change volume
- checked System Preferences->Sound settings: nothing showing up under the Output or Input tabs (no "Internal Speakers" showing up)
- NO RED LIGHT coming from headphone jack... so it's not the optical speaker switch problem most people seem to have.
- In "system information", when I look in sound hardware... no description for input, output, etc...
I've hunted and hunted all over the internet trying all various suggestions that others have had success with - I've tried all of the following, but still no luck:
I've tried all of the following in the listed order but nothing's changed:
- repeatedly plugging & unplugging different types audio equipment to the headphones port (including apple headphones)
- disk utility and run disk repair (no errors)
- tried PRAM/NVRAM resets (I don't hear the "chime" sound)
- tried logging in via a new user account
- tried deleting ~/Library/Preferences:com.apple.systemsound.plist
- plastic toothpick in the hole
- looking in the hole with microscope & 1.8mm led to illuminate - can't see anything obstructions in the hole
- I downloaded and booted the ASD software EFI and OS diagnostics - no errors
- tried disconnecting battery then rebooting
- an isopropyl alcohol swabbed q-tip cotton swab
I also went to see a Genius at the Apple Store - they did their tests and said "there's only two options:
- replace the logic board as we don't replace individual components, or
- use a USB adapter"
The logic board repair quote was extremely expensive as my warranty is over and the charge probably includes replacing all 16Gb of memory too as it's soldered in; and I said I didn't think that last suggestion was very Apple-like - I'd need to carry around an ugly USB adapter and an external speaker/mic device just to hear sound!
So I'm at a loss and need your help!
Everything else works fine on my computer, so I'm willing to get my multimeter out and start testing hardware but I'm not sure where to start (I/O card / Logic board?).
My logic board # is 820-3476-A
Is this a good question?