Washing Machine Gets Stuck, Not Draining

My washing machine will get stuck right before the rinse cycle. The washing machine will be full of water. The way to "fix it" is to twist the knob right after the "rinse" line, find the sweet spot, and pull the knob out. It can take 10+ tries to find this sweet spot and seems to have no rhyme or reason.

I've read online that this might be a drainage problem, but I'm not sure that is the case here. I'm basing that off of the fact that allowing time to pass doesn't increase the likelihood of hitting the sweet spot.

Anything I can check? As the pictures show this is a Whirlpool Ultimate Care II

Thank you