Vacuum Table Suction Issues

I have a Vastex vaccum table exposure unit. Recently the suction seems to be very weak. I can feel air coming out the side tube which leads me to believe the compressor is sucking the air. Does that compressor need any maintaining on my part?

I have looked for visible tears in the rubber and cant find any. The table isn't very old, but does have a lot of built up ink / emulsion around where the screen presses on the rubber. Could that be cause issue with my seal? It there anything else I need to look at/for when checking this issue?

Any help is appreciated. Thanks!