820-2915 No Audio on Playback

[RaezorSharp]

Hi have a 820-2915 that will beep on startup but doesn't show an audio device within MacOS and doesn't play audio thru speakers or headphone jack.

Checked U6200 Pin 6 PP4v5_Audio_Analog = 4.48V
Checked U6201 Pin 9 PP1v5_s0_Audio_Dig= 1.5V
Checked U6201 Pin 46 PP5V_S0_Audio=5.04V

Headphone Jack looks OK.

Any suggestions? Noticed someone mentioned to remove R6805 rather than replacing headphone jack.

 

[2informaticos]

R6805 does the trick if stuck in SPDIF mode.
If audio codec is not recognized in System Report, the issue is not from the jack side.
Check HDA_RST_L level.

 

[RaezorSharp]

HDA_RST_L is 1.5V at Pin 2 of R1812 (33 Ohms).

 

[2informaticos]

Compare with good board if 1.5V is good level.

 

[RaezorSharp]

Tested with another machine and 1.5V is a good level as the other had 1.51V.

 

[2informaticos]

"If audio codec is not recognized in System Report"
Did you check that?

Check all series resistors on HDA lines between PCH and audio codec.

 

[RaezorSharp]

I checked R1810,R1811,R1812,R1813,R6211,R6212 and they are good.

System Report for Audio Devices does not show any input or output, not sure what you mean by audio codec showing up in system report.

 

[2informaticos]

Try changing audio codec first.

 

[RaezorSharp]

By chance I swapped out the board with another 820-2915 and noticed that it was also reporting the same issue.....so I re-installed the Mojave MacOS and the problem is solved without any hardware.

Please close this thread.