In handheld mode it doesn t outputs audio not over the speakers nor over a headphone. In dock mode audio is present. I checked the Realtek ALC5639 ic but the only thing I could find is that the MICVDD has 0V instand of 3.3V.
Everytime I try to insert a Gamecard the Switch displays the error code 2002-2629 before the Gamecard is fully inserted. I tryed three different known good card readers. Every time the same result with the error.
Does a system update, updates the card reader also?
it’s a strange one. searching online it seems that the console would need replacing if under warranty. I take it you have tried a different game cartridge?
the sound issue is interesting. When plugged into the dock a signal must be sent either high or low to tell the switch to stop sending to the speakers and send audio down the HDMI. thinking logically the sound is always going to be coming out the sound chip and the only change would be is which way it gets routed. Maybe worth checking the tracks from the Realtek down to the Pi3USB since that routes to the USB and eventually to the HDMI in the dock.
I’m not sure how the cartridges work but I’d image there are sound files on-board that get shared to the Realtek possibly via the tegra but could be direct.
Everything points the the realtek but you get sound out in the dock so at least that side works. I’d suspect the inputs to the realtek or something along their path.
The only other thing I can think of is replacing the large IC on the other side of the board directly under the gamecard reader connector or at least re-flowing it. There is a chance that changing the gamecard reader a few times could have broken one of the solder joints under that IC causing your issues.
I tried different game card readers and the game cartridge in an other Switch. Everything works fine. The problem is related to the defective Switch mainboard.
The audio signal which passes the PI3USB (in @ pin 19 AUX- and pin 20 AUX+ and out @ pin 21 SBU1 or pin 22 SBU2) is fed direct from the soc. I don t see a connection from the Realtek ic to the usb c port. I think the Realtek ic is only there for audio output over the internal speakers and is fed separately from the soc.
there must be a switch that sits between the SOC and the Realtek and Pi3USB to tell either the Realtek or Pi3USB to output sound. Sadly I have no idea what that component is!
It’s going to be related to the USB-C getting plugged in as that is what drives the sound output and it will be the same signal that tells the LCD and backlight to switch on and off.