Issue with INMP441 mic on ESP32

Issues
1

Hi all,

I have soldered my ESP32 with 74AHCT125 level shifter and INMP441 microphone following my diagram as uploaded with this post. I have done so twice. On version is now behind my tv, which works flawlessly.
The other board seems to have issues. I am driving WS2812e LED strip.
Regular control of colour and effects do not result any issue on any of the 4 pins installed via the level shifter. However, when I select a audioreactive effect for example Gravfreq, it does not work as it should. With gravfreq, the amplitude of the signal seems to max out, lighting up the entire strip, with the white LED flickering all the way at the end. Sometimes, wiggling the wires results on a more logical pattern with changing amplitudes, but it does in no way represent picked up audio. I have tried 3 different microphones, but they all yield the same result, which makes me believe the issue is in the board itself.
Using a multimeter, I could not find any short circuits or broken connections. What could be the issue here?

On the TV version, I had not connected the L/R channel to ground, but it still works.
On the other board, I have tried both with and without L/R to ground, but this seems to make no difference.

I have absolutely no clue left on how to fix this.
Does anyone have any ideas?

Many many thanks!

Tim

ESP32 with mic b
ESP32 with mic b1920×1266 343 KB

2

bad mic? loose wire on mic?

3

Unfortunately, I cannot lead the issue back to one of these possibilities. The mics seem to work on the other board and the wires are soldered (and resoldered to be sure).

4

You also don’t have the 100nF (.1 uF) ceramic bypass capacitor by the level shifter that is in the KB.

As far as the mic, maybe you messed it up when soldering it. They can be over heated and or are just junk right out of the package. I would try another mic.

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5

I am learning every time I am on the forum. Thank you. I’ll add the capacitor.

Would you still advise to use the resistances before the LED-strip as shown on the KB as well?
My power source is a 4S 10000mAh LiPo, which is connected to a buck converter converting to 5V.

6

You likely won’t need a resistor.

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