Locate air leakes
If. not already mentioned , the best way to locate leaks, is to use a mixture of dish soap in water brushed on ( or any other application) all the couplings or connections . Small bubbles will appear pretty quickly . Saves unnecessary disassembly to check O rings and seals as that might create further issues. (If it ain’t broke ; don’t need fix’n) Once the point of a leak is found, just disassemble that part for further inspection.