When recording audio with a Teensy 4, using the audio shield and routing signals to an SD card or USB can introduce noise, depending on your connections. Teensy can also function as a USB audio device for direct recording into software like Audacity.
It seems like you're exploring options for programming the Teensy 4.1 through its pins without using the USB-micro connector. One approach is to access the D+ and D- pins on the board and solder them to a custom USB-C connector, bypassing the...