Bluetooth/wireless mighty mouse left and right click problems

Clicking with the left and right mouse buttons doesn't seem to be working properly. I first realised this when a message box warning me of low disk space popped up and I couldn't click on OK. Scrolling with the ball works, as does clicking with it. I restarted my iMac and removed the batteries from the mouse for a minute, but all that happened was that left and right clicks started acting like middle clicks. A wired mighty mouse works fine. I've tried cleaning it by turning it upside down and rubbing the ball on paper and a clean damp cloth, no change.

I suspect this is a hardware problem, but short of taking the mouse apart or taking it into an Apple store, does anybody have any suggestions? If I do take it into a store, will they fix/exchange it? I only bought it in January, but I didn't hang onto the receipt.

If I do have to buy a new mouse, I'm considering a magic mouse. The things holding me up are:

* Middle-click - I use this hundreds of times a day. Triple-tapping is slow and awkward. Any other options?

* Linux compatibility - I spent most of my time in Linux, Ubuntu to be exact. What's the compatibility like?

 

I'm afraid that's not the problem. Everything is as it should be there, and a wired mighty mouse works fine. Furthermore, the wireless mighty mouse has stopped working entirely now, the iMac can't even see it any more.

 

Nope, changed them a week beforehand, swapped them out with new ones just in case, nothing.