I haven’t. I’ll do that. Thanky!
Yes you get 3-4 a day on high drop then it lowers VERY low for the rest of the day.
This is slightly frustrating. I got 6 yesterday after I dropped the quest and picked it back up. Still nothing today and I’ve killed humanoid rares, etlites and normals, committing mass genocide of bad humanoids in assault zones and throughout questing zones while doing world quests.
Grr.
Just do what I did, I got whatever I got daily between 3-6 and eventually quest completed from doing dailies. You’ll only face more frustration if you try to grind them out at the low %.
I just assumed I’d get something today after doing all of my dailies and emissaries and the assaults. Oh well. Thanks. 
I’ve been farming humanoids for 2 hours now, and I have yet to see a single echo. I’m still at 0/40. I’m not sure how folks got 4-6 right off the bat
IDK how it works, it seems like sometimes you can get 4-6 quick and then boom, nothing and some days i would get nothing at all.
I just got them from nagas in Nazjatar. Maybe 2-5 each day. Once they dropped for the first time each day, they’d stop dropping entirely for me.