Inbro RSC-1201 air leaking

So I'm learning on my inbro single needle and I'm just wondering if anyone has some experience with this machine and can help me out.

It seems like it is constantly leaking air from the threading cylinder block. I noticed that the valve for thread 6 has a slot machined into the block, and that's where it is leaking from. Is this supposed to happen? I find it hard to believe that this is okay because it has my compressor turning on the refill every 5 minutes.