Hi,
We had an issue of our custom build boards were the application firmware could be programmed, but the modem could not be programme because of the error "RootKeyDigest IPC timeout".
We were able to disassemble the board and noticed a solder bridge between pins 96 and 97 (both RESERVED) on our nRF9151. Could this short explain why modem firmware programming fails with a RootKeyDigest IPC timeout, while application programming over SWD still works?
Unfortunately the component broke in the disassemble process, so we cannot reflow it. Before moving into production, we'd love for you to be able to verify that a short of these two pins could cause the above issue.
Best regards, Patrik