BBB based board power-off


We have a custom, BBB based board, which, when all relevant patches and PMIC settings have been applied, will power-cycle when poweroff is issued (remains off for a couple of seconds, and powers on again. The strange thing is that if we have the UART0 Tx pin connected to a PC, when poweroff is issued, the board powers off normally. Apparently, connecting the Tx causes some bleed that drops the voltage levels, that otherwise do not fall off adequately fast. Would anyone have any ideas as to what could be done to resolve this?

Thank you.