Did I fry my speaker output? Is there any way to repair it?

Im currently in the state of building my first saber and Im using a proffie board.
Once I Connected all the wires I put the battery in. The boot sound started playing but suddenly stopped. After this every time I put the battery back in there was no sound.
The lights and the buttons work just fine, the SD is working and on the Arduino app I can see and install everything. The issue isnt with the speaker, I tested it independitley on a receiver. So my question is did I fry the sound output? Is there a way to fix it? How can I find the exact cause? Or is there a mute function that might be active?

Here are some pictures of the board. I removed it from all of the wiring and soldered these 2 pins to it to test the speaker. It doesnt look damaged. It wont play sound though

The config file might be useful as well. Although I dont think its a software issue

I don’t have much contrast but it looks like Q3 Q4 and/or Q7 might be blown. Typical of a short on your connections. Since you connected on 4 and 5, I’m tending to think is Q7. But that’s all I can say.

is this gunk that cleans off or exploded chip?

Great eyesight. You might be onto something here. Baldusi stated that Q7 might be most likely be blown. I took a quick look at it and you could be right I’ll take another look on it tomorrow in bright light. Gotta find out if it’s possible to replace. I’ve never exchanged a chip this might be beyond my capabilities.

Might need somebody to do it with an airstation. But it’s totally doable. Incidentally, I think it’s typical of an inverted circuit.

Generally, inverting the battery input should not damage Q7.
However, shorts might.

To start troubleshooting what is actually wrong, start with checking the serial monitor to see if the CPU is even responding. Also, grab a multimeter and check if you have 3.3v between the 3.3v pad and the GND pad.

If the CPU is working well, type in “on” in the serial monitor and see if it says anything interesting.
Also, try “get_volume” to make sure it’s not muted in some way.

Then, while on, check the voltage between GND and 5v (should be 5 volts)
Finally, switch the multimeter to AC and measure between the two speaker pads. (Should see at least one volt AC.)

If you get to this point without finding a problem, try a different speaker.

Thank you for you reply. First off the „dent“ wasn’t a dent on the Q7. Just a stain from the soldering paste or so. Needed day light and a magnifying glass to examine it.

I tried your diagnostic measurements. The CPU has no issues it detects swings clashes and so on in the serial monitor.

Between 3.3V and GND there is 3.3V
However between 5V and GND there is just 260 mV while powering it via micro USB (not sure if it needs a battery connected to output 5V or if this is the error)

Between the speaker + and - there is constantly 0V

5v booster is only activated with battery power and when the blade is running.
0V AC at the speaker is not good though. The pads are fed from components right next to them. Do they give you anything?