Came out to investigate noise coming from master bedroom. Upon arrival customer let me know this is not the same tapping noise we previously dealt with. He told me that noise is virtually gone now and he is satisfied with result. Showed me video of new noise and it sounds like blower motor humming coming from return vent. Checked air handler in heat, cool, and fan only. Blower amps fluctuated from 1.00-1.04amps (motor rated for 2.5) which is normal. Blower capacitor rated for 15mfd and reading 15.8 which is also good. Visually inspected full air handler, blower housing and fan blades do not see anything obstructing at this time or means for concern. Was not able to simulate exact humming as the video he presented. Did make customer aware even though PSC motors are set to a certain speed, the noise can fluctuate based on the load and airflow but the humming is normal. Did mention that nowadays new equipment has variable speed motors that operate way more efficiently and with less noise.