I recently found that using the md380tools from Travis Goodspeed I was able to apply a more feature-full firmware and found instructions on how to reset the password.
The reset hasn't worked for me.
The instructions to reset can be found at:
I unfortunately still have issues.
After reading some more, the new firmware allows one to update the DMR ID without needing to program it.
Also, I found the best results by using a raspberry pi with the md380tools.