iMac ringing
My iMac suddenly starting getting wonky, for want of a better term. I could not scroll with magic mouse - I would start to scroll and then the scroll bar would rapidly move to bottom of screen. If I tried to scroll back up to the top, it kept going down to the bottom again. I was able to click on the icon for my home screen and successfully got there. But again the scrolling downward began, sort of like a magnet was attached. Quit Safari. In Finder, clicked on Help. The search bar opened and the magnetic force (whatever) went to end of field and said something like 'no results found'. (Indirect quote) I had not even typed anything into the Help search field when it did this. Then, and for me this was the scary part, a loud ringing noise started going off. Sounded like an alarm. Somehow (sorry, didn't occur to me to take notes) I was able to get to the Support Community to see if anyone could help me with either the scrolling issue or the alarm. I promise if this happens again I will take step by step notes. It's just that one doesn't expect an alarm to go off so one wouldn't be taking notes.
I did have the scrolling issue in the past and although I asked the community about it, I never got a satisfactory reply. Was told that it had to be my mouse. Period. Now it might be the mouse and maybe I didn't understand. But what would cause a very loud alarm to start?
iMac mid-2011
Yosemite OS 10.10.5
Safari 9.0
No other hardware that might cause interference: no laptop, no iPhone (sigh), no nothing. Even have printer turned off and unplugged.
And I really don't know where to post this other than OS X Yosemite. Really, really have no idea what Category to select. Feel free to redirect. Thanks.
iMac, OS X Yosemite (10.10.4)