I've heard the bb creak sound here and there for the past few months but very randomly/sparingly.

Now its every other pedal stroke. I took the chain off and spun the cranks, no noise. Cleaned and re-greased chain, sound is still present. My chain tension is 1/2" or so slack. The bb doesn't feel crunchy but it def. sounds like the bb creak sound, I don't know what else it could be. How do I know for sure?

Its a phil bb.

Thanks

check everything
-chainring bolts
-pedal threads
-crank bolts
-BB cups

Phil's sealed bearings are some of the best at keeping the gunk and water out of the bearings.

Every noise seems to emanate from the BB shell.

Pedal bearings, primarily the side that makes the noise. Chainring bolts, seat rails, crankset-BB interface.

Generally, bad BBs won't creak without a chain, unless they are under load---chain---or really F****d.

Would suggest an overhaul, new grease on the seatpost, pedal bearings and the like. If noise is still present, Phil can replace the bearings for a nominal fee and send it back to you.

Take out BB, clean everything well, regrease everything well, re-torque everything to spec.

Does it creak when you are out of the saddle?

If all else fails you can't place the bike horizontally and drip a very small amount of lubricant and get it to seep through. I say this because you mention the noise comes from the BB shell, maybe the BB is slightly off.