Another note worth mentioning is that when a tradable card is shuffled into the deck while Augmented Elekk is on board, Elekk will MOST of the time shuffle in an extra copy, but not always.
I had a game just a moment ago where ~3/8 tradable shuffles did not shuffle in an extra copy off of Elekk, which kinda made me the big sad if you know what I mean.
Anyways, I appreacte y’all.
Tentacle monster, signing out.
Did you draw your entire deck to be sure?
On multiple accounts, yes.
I had to leave at least 1 card in the deck, of courses because otherwise the tradable effect doesn’t work, but when you trade the card and Elekk’s effect DOES trigger, the trigger symbol underneath the minion hilights, also you see the shuffle animation go over the deck, and it shows up in the History Bar as well.
This would work the first couple of times usually, but then after ~3-4 shuffle attempts (in which you’ll see the deck size increase after each successful attempt), it’ll stop working occasionally, then work again.
It’s almost seemingly random, but yes, I’ve checked over everything and it’s clear the interaction here is bugged.
Is there any chance your deck was full? If I recall correctly, the maximum deck size is 60 cards.
No. Each time I performed this combo, my deck was down to anywhere from 2-5 cards roughly on average.
It was near empty SPECIFICALLY so I could keep cycle shuffling Persistent Peddler, and yet as I monitored the deck size after each shuffle, some shuffled worked with Elekk and others did not.
There didn’t seem to be any pattern to it either, other than the first 1-2 tended to go off consistently.
After that, flip a coin.
I think I’ve seen this as well while trying to complete the various tradeable achievements. I haven’t paid enough attention, though. I’ll start now.
I’ve definitely seen it. It appears to be related to how quickly I trade them in, but I could be wrong about that. I haven’t ran enough trials. I completed those achievements so I won’t be. 
I completed them too, but that doesn’t change the fact that the interaction is bugged.
Definitely. What I meant was “I won’t be doing more trials.” It should still be fixed.