B2601 mower deck always failing down

[Tractor_Chunks]

I must be doing something wrong or need to fix something. The mid mount mower on my b2601 is always finding its way down to a lower setting.
This happens in two ways:
1) I'm just mowing normally and I think the anti scalp wheels are sometimes hitting the ground, this bouncing the deck up a bit and I think then the height adjustment knob has a chance to rattle to a lower setting.
2) I have the deck on while using a 3 point attachment and the up and down of the 3 point lets the knob move out of the top setting. Before I know it, the deck is dragging on the ground.

What do I need to do here to fix these things? I forgot to take a close look at height adjustment under the tractor before I put her to bed, but figured it couldn't hurt to jump on here and ask.

 

[Tire Biter]

So the height adjustment on these things is just a plastic cam. There‘s click stops on the adjustment shaft. Sounds like either or both of those is worn Letting the adjustment to slip down. It’s a hokie setup. I’m not a fan of suspended decks anyway.
but i’d bet on yer plastic height adjustment cam being worn out.

 

[Tractor_Chunks]

It's a new tractor and it did this from day one. I believe the cam is actually metal. There must be a smart way to fix this. I'm surprised I didn't get a bunch of suggestions here.

I'll try to take a closer look at the mechanism and see if any fixes are obvious to me.