How can I reduce the noise from an air handler unit?
I have a Goodman AR42-1 air handler unit in an open closet. The setup looks like this:

When the air handler activates it sounds like this:
Current sound levels:
Everything off: 36 dB
A/C on and inside closet: 63 dB
A/C on with door closed: 59 dB
A/C on in Living Room: 55 dB
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