I do not have the answer, but looking for the root cause for this issue.
I do not have the schematics for the 3DS or 3DS XL however this seems to be a common problems for many users.
My approach to try to find a fix:
- Sound IC: It is ok, when checking with earphones sound is ok.
- Earphone jacks: Suspecting that could be in short and motherboard sensing earphone all of the times. In my case earphone is ok.
- Speakers flex cable: This flex cable is used as well to produce the 3D effect and camera sensor. So, discarding it if having 3D effect.
- Volume switch: Easy to verify with a multi-meter, in my case working properly.
At this point I do not have clue other that believe that at motherboard level there is a short in the line feeding the speakers.
Does any one have a clue where to look for or what to replace ?
Regards,
Juan