Complete 1 system preventative maintenance and system repair. Air flow noise as well. Found system max set for single stage cooling at 900 cfm. Set the cfm to around 1100 cfm on single. Turn 1 zone off on master and drop the cfm on kids bedroom to 900 cfm until it hits the next ramping profile to 1100cfm. Owner gonna test this for now. If still not comfortable then we will have to put a bypass damper and adjust the stages of cfm accordingly. The system is cooling normally.