rough shifts

[07PSD]

for the last few thousand miles my trans has has been shifting rough. i found that if i let the trans get up to temp before driving it shifts a lot better but still not smooth like the 5r110 should do. what seems weird to me is that if i start driving before its warm its at its worse but at is warms up it doesnt shift any better. just doesnt make sense to me because as i said before, if i let it warm up before i drive its pretty smooth. also when i shift from drive to reverse/ reverse to drive it seems to take a little longer than it used to but nothing too serious (still under a second). i was maybe thinking to start with the dd solenoid.

i checked the fluid a few weeks ago and it was a quart low so i topped it off thinking that would solve my problem but its doing the same thing it was before

any help with this would be greatly appreciated, thanks