Letters keep repeating, even if no keyboard is attached

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Level 1

8 points

Letters keep repeating, even if no keyboard is attached

Out of the blue, letters start repeating on my Mac. I tried changing the keyboard and rebooting, but nothing seems to solve the problem. Any application I go into that receives input will see the repeating letters. If I do type letters myself, they will be displayed in between the repeating letters. It's as if one key is stuck, but it could be a kkkkkkkk or a aaaaaaaaa, there is doesn't seem to be a pattern. It almost seems like someone is controlling the computer via a VNC client, but this does not seem to be the case. Any ideas? Could it be a virus? What should I look for?

Thanks

mac tower intel

Posted on Apr 12, 2011 6:44 PM

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Answer 1

BDAqua

Level 10

251,359 points

Apr 12, 2011 7:11 PM in response to marloma

Hi marloma, and a warm welcome to the forums! 🙂

After starting does it continue if you disconnect the Keyboard & Mosue?

Shut it down. Disconnect any periperals, printer Monitor Ethernet, USB, FW, etc., then Reset the SMU...

http://support.apple.com/kb/ht3964

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Answer 2

Apr 12, 2011 10:38 PM in response to marloma

Hi, marloma -

As BDAqua has indicated, a peripheral device may be sending a bogus signal which the Mac's software/hardware is interpreting as a keystroke.

When disconnecting peripherals to try to isolate the cause, include removing all USB and similar cabling - it, too, can be suspect (I had a cat once who liked to chew on cables; occasionally his fangs would cause shorts in the wires).

It could also be caused by a clump of dust or dirt in a USB port, causing a short (some dust/dirt can be electrically conductive). It could even be a bent pin/contact in a USB port.

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