XPS 15 9560 with no sound

Question

I am working on a Dell XPS 15 9560, Win 10, which has no Realtek audio device. It is not listed in Device Manager. Intel HD Audio is there and I do get sound if I connect an HDMI cable to a TV but the laptop itself will produce no sound and I get no sound from the headphone jack. There is no audio device to select for default output and recording in the setting in Windows. I ordered a replacement audio board from eBay and installed it but still no sound. I pressed F12 to enter the diagnostics system and tried testing the sound there but there was no sound generated. I made sure that the laptop's internal speakers are plugged in. I checked the UEFI settings and made sure that the audio system is enabled. I tried disabling and enabling it just to be sure. All Windows updates and optional drivers have been installed and I tried installing the Realtek driver provided by Dell for this model of laptop but still no Realtek audio hardware is listed in Device Manager. What can I do to get the sound working again?

Wiklen · Accepted Answer

With some generous assistance from someone I was able to do a board level repair which fixed this laptop. The RA77 resistor had disappeared from the board somehow, which resulted in a broken circuit,  and that was preventing the audio codec chip from being powered. I ordered a suitable replacement and soldered it on using a hot air station. Now the audio completely works.

d5123101 · Answer

When/how did this issue start? The fact that the BIOS diagnostics show the sound system does not work means it is probably still a hardware issue not a software issue.

Wiklen · Answer

Unfortunately I have no information about how this issue started. I work at an electronics recycling business. Sometimes we get things that are worth refurbishing and selling. This laptop, we hoped it would be fixable.

d5123101 · Answer

Sounds like an issue with the replacement audio board/its connection to the motherboard. At best you could fix it with troubleshoot, at worst you sell the laptop as sound not working.

Wiklen · Answer

I also suspected the replacement audio board wasn't working, the same as the original audio board. I contacted the eBay seller and asked if the replacement was tested. They didn't answer my question but did say they would send another.

d5123101 · Answer

Okay let me know how it goes

Wiklen · Answer

Unfortunately the 2nd replacement board didn't fix it either. I'm looking in to other possibilities like maybe something is fried on the mainboard so power isn't getting to the small audio board.

d5123101 · Answer

Yeah these niche types of repairs are difficult to pin down, might be more worthwhile to sell the laptop without sound.

Wiklen · Answer

I might try doing a board level repair on this one. I've never tried that before but with only one component, the audio, not working I might be able to figure it out. I don't think anyone would want to buy it from our store if it doesn't have working audio. It could be worth something on eBay to those people who do board level repairs if I decide to not mess with it.