OR Ferrosi Pant/Short - Sizing Puzzle

I'm 6' 180 lbs, I generally wear a size 34 pant, but have slimmed down in the past few years, so I might actually be closer to 32" waist at this point. I've been buying Ferrosi on the secondary market (MP, Poshmark, eBay, etc...) and I cannot for the life of me figure out the sizing. I have a few pairs of 34" Ferrosi that are so loose I've had to take in the waist by 3-4 inches. So, I bought a pair of size 32 pants that were still kinda loose (but not egregiously so). Eventually, I find a deal on a pair of size 30" shorts (I'd never try a size 30 for anything else) and they fit great! The waist is perfect, the legs are trim but not tight. They work both casual and mountain biking. Cool, I figured it out! 

I order another pair of pants off eBay in size 30, and I can barely get them buttoned and the legs are skin tight. WHAT GIVES!? 

I've even double checked the tags and they have the same OR "serial number" and "year" S17  

Has anyone else run into this, or am I just finding weird stuff.

I have 2 pair of OR shorts. One is nearly 2" bigger than stated, and baggy. The other is super snug and slender. I don't know if they're the same model though; I got them several years apart.

Yeah, the 3 I have are all big.  Thank goodness for the drawstring.  I like the material enough that I tolerate the sizing discrepancy.  

Okay, well at least it's not just me! Thanks for the confirmation.