Left shift key inserts ± (plus/minus symbol)
When I try to use the left shift key and hold it down for more than a half-second or so it will insert the ± symbol. ±(it just did it again!) This has rendered the key useless (besides being a shortcut for that symbol, of course). This occurs in all profiles.
I am using the standard Matias wired keyboard for my iMac running Yosemite (OS)
What is going on?
HELP!!!
Any ideas on how to remedy this?
iMac, OS X Yosemite (10.10.5)