ZF 8 speed rpm goes up and down until warm?

Ever since I've bought the truck over 25k miles ago, my 2014 Ram 1500 rpm varies up and down until warm while in low rpm. As soon as the trans is warm it drives normal and have no issues. Never gets any worse but some days it really pisses me off. It seems like a tuning issue. Any info? I'd pay to have it disabled. I've tried to research this issue multiple times but have never seen anybody ask the same question. Don't believe it to be the torque converter because it seems like if it were bad, it wouldn't go away when warm. 140k miles on it currently. Again, has done it since I've bought it and never got worse or better.