Why not just get another and leave it hooked up at home to the PC so when it restarts you will see what is the issue.

Found the cause. USB drive needs to be formatted as FAT. Mine was formatted with exFAT.
Be nice if that was in the README file.

When you device is acting as an MSC and plugged into your PC why dont you just copy over you firmware's bin file to it and have it read that and flash itself?

I would think the example should work out of the box though.

ESP v5.3.1 I created a new project using the example USB/HOST/MSC https://github.com/espressif/esp-idf/tree/release/v5.1/examples/peripherals/usb/host/msc When I run it and stick a USB stick in i get the following in the terminal. Its failing on this line: ESP_ERROR_CHECK(msc_host_vfs_register(msc_d...

Along this concept. I saved my 3 .bin files files files to a SD card on the Master.
bootloader.bin
partitions.bin
firmware.bin

Would the correct method be for each file ?

esp_loader_flash_start
esp_loader_flash_write
esp_loader_flash_finish

Yet again. Im not saying that esp32 is bad, because i have poor results. I am not expecting any results from bigbanging code. The point is that esp32 S3 with 160MHz has similar results as P4 with 360, and S3 with 240MHz is performing much better. Its just observation, nothing more. FWIW, I get what...

This is very interesting. Thanks for sharing.

Are pins 2 of L1 tied to GND. It does not look like it from the photo to me.