so the other day i started noticing my BOV (yes i have a BOV on my supercharger) stopped whistling and then i was looking at my boost gauge and im not make any boost so does this mean im not building pressure and what could be the problem

 

Check your Belt! it could of gotten loose, even when you look at it, it could seem tight, but if its not tight enough, the belt could be slipping and not producing any boost, therefore you wont here your BOV.

 

Is it a CTSC kit? My friend has one and he said the BOV had a leak. Check that. He welded on a new bracket and a tial and the problem went away

 

Check belt, look for obvious leaks and if both those are fine do a boost leak test and see if it losing pressure somewhere.