[Help] New 3DS XL with no sound with (possibly) water damage

[AveX9]

So as the title says, I've got a pearl white new 3ds xl from Japan with a particular quirk, it has no sound whatsoever.
Usually I bet on a damaged speaker/ flex cable so I replaced the screen (it was bad too) and the speaker+3D Flex cable for a working one (yes, i tested it beforehand on another unit). Turned on the console and no sound. I plugged some headphones (which I was expecting to work) and still no sound. I visually inspected the board and found some gunk near two ICs (see pics). One is next to the headphone jack and the other is neat the cartridge slot FTP connector.

All I need to know is:

• Which is the chip in charge of sound in the New 3ds (I've got many donors so I can harvest one if necessary)
• Has anyone experienced this? How fixable do you guys think this is?

I'm not an electrical engineer but I'm a technician so I'm kind of lost as to which one I could blame and what to do next as I don't usually deal with water-damaged consoles. Please note that everything else works fine.

Help me please

 

[AmandaRose]

OK so you said the 3ds could be water damaged. Did you check the water damage indicator on the PCB as that will then let us know water damage is to blame.

 

[The Real Jdbye]

So as the title says, I've got a pearl white new 3ds xl from Japan with a particular quirk, it has no sound whatsoever.
Usually I bet on a damaged speaker/ flex cable so I replaced the screen (it was bad too) and the speaker+3D Flex cable for a working one (yes, i tested it beforehand on another unit). Turned on the console and no sound. I plugged some headphones (which I was expecting to work) and still no sound. I visually inspected the board and found some gunk near two ICs (see pics). One is next to the headphone jack and the other is neat the cartridge slot FTP connector.

All I need to know is:

• Which is the chip in charge of sound in the New 3ds (I've got many donors so I can harvest one if necessary)
• Has anyone experienced this? How fixable do you guys think this is?

I'm not an electrical engineer but I'm a technician so I'm kind of lost as to which one I could blame and what to do next as I don't usually deal with water-damaged consoles. Please note that everything else works fine.

Help me please
View attachment 335437View attachment 335438

If the speaker or LCD flex was bad, the console would power off immediately, so it wasn't necessary to replace them.
Looking at the iFixit teardown (https://www.ifixit.com/Teardown/Nintendo+3DS+XL+2015+Teardown/36346), none of the chips there seem like a likely culprit, except for maybe the Texas Instruments AIC3010D "possibly codec IC", marked in red in this picture:

https://guide-images.cdn.ifixit.com/igi/IKlW6WTZKKmapYkt.huge
Could be one of the unidentified chips, not all of them are marked in the teardown.
Could also be the audio output connection on the SoC itself is bad, for your sake i hope that's not the case since it's probably BGA, you can get lucky and reflowing will fix it, but it's also likely it will make things worse, and reballing is probably out of the question.

One trick I've seen people use for devices with a suspected bad audio amplifier IC is to trace back the connection from the speakers or headphone jack, find a point in the chain before the amplifier and probe it with a speaker element with one wire connected to ground to see if any low volume audio is audible, do the same thing at a point directly after the audio amplifier, and in that way confirm if the amplifier is bad or if there is any audio being generated at all. But I don't know if the n3DS XL has a separate audio amplifier IC, there just isn't enough information in the iFixit teardown and you can't find datasheets for some of these parts.