Analog input stability

vincentiu:

  1. It's tennsy 3.2 so it has this resolution

Why didn't you tell it's a Teensy before?

  1. now it's better?

I think you forgot to post your updated code.

it can be higher then this, you recommend even numbers, right?

We normally recommend powers of 2 as that's how computers work, so 4092.
But 4092 distinct values from a regular pot? Not much chance to get that perfectly stable. Vibrations from you touching the table may be enough to jump a few points up and down. The higher the resolution of your ADC, the more noise you will see.