Why would the bootloader NOT mount a USB device?

[vivek-pai]

I have a custom board, based off of the Bluefruit. I can build and flash the bootloader just fine (in WSL). It loads*; however, I don't see a USB connection in Windows nor does a USB drive appear. My custom board does load 3x USB drives if I flash the nrf5 SDK MSC sample,

make BOARD=myboard
nrfjprog -f NRF52 --program myboard-0.7.0-21-g38b8a30-dirty_s140_6.1.1.hex --verify <-- after erase, attempted with all forms of erasing (eraseall, recover, sectoranduicrerase, sectorerase)

I tried building and flashing the PCA10056 bootloader on a nRF52840 DK. Same issue. However, if I flash the release hex (0.7.0), the USB drive appears as expected (with the Windows USB ding).

This leads me to believe that I'm somehow building the hex wrong.

What am I missing?

*I confirmed that it loads by adding PRINTFs to trace through bootloader code and observing in RTT. It just continually prints in wait_for_events and appears to call tud_task().

EDIT: Looks like the hfclck never starts. nrf_clock_hf_is_running just returns false here