@janskallerud I hear you! Exactly my issue - nighttime airway noises, sometimes I sound like a squeaky door. If I hear those rattles after I lie down at night I know I am in for a restless sleep.

I wish an inhaler would replace the extra session but I have yet to find one that doesn't turn the phlegm into cement. The first night or two on a recommended inhaler always feels pretty good but the gunk dries and builds up.

After a lot of experimenting, the good news is that I found that an extra clearance session right before bed is helpful. The bad news is that it's an extra session and I can't use a bronchodilator before, so the clearance can be time consuming. Working to decrease the time! Postural drainage has been helpful. Your mileage may vary but I found mucinex (guaifenesin) and NAC made night-time rattling worse. You'll likely need to experiment to see what works for you.

So my (present) routine: levalbuterol and 7% saline morning upon waking.; levalbuterol and 7% saline prior to dinner; autogenic drainage and active cycle of breathing and postural drainage before bed. Very little gunk comes out but apparently enough to help keep me rattle/cough free. Movement exercise during the day I find makes clearance sessions easier.