It's possible both of your mice need cleaning.
http://docs.info.apple.com/article.html?artnum=302417 How to clean your Mighty Mouse
Take a piece of bright white paper, turn the mouse upside down on it, press down on the ball, and run the mouse quickly in circles over the paper. This will remove all the gunk that's building up on the ball
TIP: To get to the gook inside the scroll nipple use a
plastic toothpick.
"Other Options:" Wear latex disposable gloves. A box of same can be purchased from your local Dollar Store or Pharmacy.
Some cell phone leather cases actually fit right over the Mighty Mouse.
Clean/wipe the Mighty Mouse off with a damp cloth/rag prior to going to bed each evening.
Some users have found using the small alcohol pads quite successful. These can be obtained from any drug/pharmacy or Dollar Store.
Only do the following if your warranty has run out:
Cleaning inside and dismantling the Apple Mighty Mouse
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If so, then I suggest (if your 1 year warranty is not up and/or you have Apple Care Protecton Plan) you call Apple Tech Support & ask for a replacement.
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Mighty Mouse Take Apart Photos
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Or you can invest in one of these:
The above can be purchased from
iSkin