Shutter under acceleration in second gear

Hey everyone!

I've been mostly lurking here for a while, not a guy with many words most of the time. But anyway, I've got a 2015 Corolla S 6spd I bought used from the deal, so I'm the second owner now. I've had it at the dealer a couple times and first they said tire balance, then they changed the front axles (under warranty), but my problem is still there.

It's faint most of the time, but the issue is, right after shifting to second, while accelerating right between 30-40 km/h, there's a momentary shutter/vibration. It's bothering me, and I'm wondering if anyone else has experienced this at all? I've still got a little more than a year left of my ecp plan and if there's any info I can pry to help get this fixed that would be cool. Hoping whatever it is, is covered under warranty anyway, but if not, well it's only money right?