Bingo. You're right. The sudden pressure change is causing foaming. The c-clamp pinch method hasn't worked consistently for me since the first pour that inspired the valve idea, unfortunately. I'll look into the idea linked above as well as continuing to seek out proper line, but I'll likely...
I've just tapped my first keg a couple of days ago and have been unfortunately having foaming issues!
The background:
-being impatient, I carbonated in a hurry for this first batch with the 30psi+shake method, then reduced to 12psi for this red ale
-using a picnic tap with 3ft of proper...