What usually helps is powering off and removing the battery for several seconds, until all capacitors are void of rest-electrons. You may try that. Admittedly it is not convenient since you have to set date/time again on bootup.
am not an expert but i think ur bootlogging or whatever is in charge of booting is faulty. y dont u flash ur emmc with vanilla then flash rootfs with combined. combined should testrun bootlogging