Sony WF-SP900 Help Manual page 130

5.
Remove any moisture from the terminals and surface of the player with a soft, dry cloth.
6.
Pat the headphone sections softly against a dry cloth about 20 times.
7.
Pat the areas around the buttons of the player softly against a dry cloth. Repeat the patting about 30 times.
8.
Place the player on a dry cloth. Then, leave the player at room temperature for 2 to 3 hours.
9.
Store the player inside the charging case once the player is completely dry.
Note
Do not apply strong force to the mesh sheet. Doing so may damage the mesh sheet.
Do not rub foreign substances on the mesh sheet. Doing so may push them into the player. If water or foreign substances get
inside of the mesh sheet, the player may become damaged.
Instructional video
The following movie shows you how to care the player.
http://rd1.sony.net/help/mdr/mov0006/en/
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