I finally had a 9V crash, it was with the pre-compiled Letux 4.9-rc5 @1.5GHz, but I wasn't trying to trigger it. I was simply using the EVM as distcc server (helping to compile a kernel on another board) while git cloning the github Letux kernel. Maybe the I/O "helped" here. Unfortunately, nothing was outputted in the serial console nor the syslogs.