I pulled apart my ALDI wireless earplugs. They're decent but number right broke.
It looks like there is some test pads on it >:)
Pins are: TX/TR/GND/RX/SDA/KEY/RST. I suspect a serial interface, no idea what KEY/TR is for. SDA is a bit useless without SCL, that might be hidden on the other side but I doubt it.
I might connect TX/RX and see what happens. What could also help is disconnect the battery and reconnect it. Maybe charge it manually? It did go flat before the thing went a bit weird.
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