strange failure of wireless keyboard
The wireless keyboard on a Mac I support has failed, strangely. Some keys work correctly. The single-quote key does nothing. But clicking the "g" key will result in a single-quote appearing -- usually many of them, repeating endlessly --or as long as I could wait-- until I press anither key. Sometimes the single-quote appears singly while typing a string completely unrelated characters.
This an aluminimum keyboard, product ID 0x239, firmware revision 0x50, supplied with a mid-2010 iMac Core i3 3.06GHz (imac11,2). No physical damage seems to have preceded this problem. The keyboard appears to be connectiong normally. Tried putting in new batteries. Checked Universal Access for keyboard: everything is off. The wireless Apple trackpad used with this iMac is, meanwhile, functioning normally.
Choosing "Setup Bluetooth Keyboard" at the bottom of the Keyboard Control Panel leads to an endless unsuccessful search, which seems strange, but maybe this fails because this keyboard is already connected (linked? paired?) -- or because the keyboard is crazed and not responding consistently.
What's the best way of proceeding? An old wired keyboard I connected to the system works fine.
But the owner prefers the smaller, wireless type. I have a spare wireless keyboard that came with a Core i5 iMac that's in operation on a nearby desk. If I understand correctly, that keyboard was delivered pre-paired with the Core i5 machine. Is it worthwhile de-pairing it and then attempting to pair it with the Core i3 machine? If that combination works correctly, then I'd guess it is time to declare the failing keyboard hopelessly demented and put it in the recycling bin. Yes? Or, what?
I'm a hardware/software tekkie, but I don't know anything about Bluetooth or these keyboards.
TIA