Marshall Monitor II A.N.C. Wind Noise in One Earcup

To confirm the symptom, observe if the wind or whooshing noise occurs exclusively when the A.N.C. mode is active. Verify that the sound is localized to one side by toggling A.N.C. to 'Off' or 'Transparency' mode. If the noise ceases immediately upon disabling A.N.C., the issue is confirmed to be an artifact of the active noise cancellation processing loop.

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