How to maintain the sound quality of your microphone
Dust, perspiration, lipstick, moisture, etc. gradually but dramatically deteriorate any microphone's sound.
However, all you need to do to maintain excellent sound for many years is clean your mic regularly.
Use:
methylated spirits or alcohol to clean the microphone body and the wire-mesh cap.
70% isopropyl alcohol or soap suds to wash the windscreen and allow it to dry overnight. (An instruction sheet is included in every AKG microphone package.)