When laying down, i can hear "fine crackles" when i inhale only. open mouth and it gets louder. no fever or breathing issues, no history asthma. what?

Some basics: The crackles you hear are likely the opening of tiny airways leading to air exchange within your lung. This can be part of under-inflated areas or a sign of fluid retention in lung spaces. It can also occur in asthma & infectious states. As long as you are functioning okay you have time to schedule a visit with your regular doc to check this out. I would not ignore it. It may be a warning.