My Bridgeport CNC mill has recently been having problems with air pressure. The air compressor is at the right psi, but the machine itself isn't. I also have not found any leaks. We have tried to raise the psi from the back of the machine, but tightening or loosening the knobs at the top of the gauges doesn't do anything. In our manual it says that one of the gauges should read 10 bar and the other 4 bar I believe. I have 6 on one and 2 on the other. Any ideas on how to fix this?

Thanks,
Dustin