I would check the fluid level when warmed up or hot in neutral and wait 2 to 5 minutes and check it shut off and then look at the level on the dip stick cold the next morning before running and se if the level ls stay the same or if it goes up further on the stick
My thinking is maybe it is over full when warmed up or hot and frothing the fluid when warmed up
It is probably a sticky valve in the valve body