Interesting! My buddy just dumped a batch that had the same problem. He has made it a few times and it has been fine. In the past all of his has be low to no head but still had the "fiz" to them. The only thing he did different with the one that wouldnt carb was use 1056 instead of wlp028. 1056 batch was seriously lacking body and carb of course.
It is strange. I do know that whiskey can be carbonated so i question the whiskey being the prob. I am taking a brewing science course and will ask to see why this could be.
Could you by chance give us your recipe with all the details? Also if you know your water concentrations/ppm? off the top of my head i believe there is a chemical reaction or enzyme that catalyzes carbonic acid which could cause disassociation or not dissolving but i am probably wrong. it just doesnt make since. Ill do a little research.
26 lbs 2-row
1 lb C80
0.75 lb black malt
0.25 lb chocolate malt
0.25 lb roasted barley
I used wlp002 from a 2 L starter.
Not sure about the water or ph. Although I don't have to adjust my water because it tastes good and I've never seen the need.