Kubota KX 121-2 Boom up stops responding

Good day all

My KX 121-2 boom up stopped responding intermittently. When this happens the hydraulic fluid is at operating temperature. Everything works normal when fluid is cold. When it happens I hear chatter at the control valve. I switch the TPSS to switch the boom up control to the left and the problem follows so that eliminates the pilot valves. I haven’t ran a pressure gauge over anything yet. I'm guessing it’s a pilot circuit issue (pilot pressure). I recently added a few attachments with actuators/ cylinders so I may have air introduced into the system. I am going to do some bleeding once I get back to the machine. I’m open to suggestions/ides to minimize disassembly.

Thanks