Whining noise and shift issue

2017 grand caravan sxt. Engine/trans makes a whining noise. The noise gets louder when I give it the gas. It doesn't make the noise when cold. The transmission would,and still on occasion acts up. By that, sometimes it gets stuck in second or third gear. Most times I can shift manually. The times that the computer won't let me shift, I have to pull over and disconnect the battery. I haven't had to pull the battery cable in a few days. The warranty expired 5k miles ago. I plan on changing the trans fluid and filter next weekend. I believe the noise is old fluid and possibly a clogged filter. Anyone else have an idea what can cause the noise? The transmission shifting issue, I'm assuming is a bad trans computer.

Edit: I forgot to mention, the transmission acts like it's slipping and makes the whining noise when warm. Putting it in park, turning it off, then cranking it, causes the noise to quiet down and the transmission works like it's supposed to for a while.