Keyboard not working *correctly* in command-line interfaces

Question

So, I've been dealing with a bit of an annoyingly bedeviling problem for the last few days, and the symptoms are so weird that it's difficult to search for people who are having the same problem - so I figured I'd post here and pray someone has had the same problem and has figured out how to fix it. The Problem:  Basically the keyboard does not work correctly in a command line interface - the moment you type any key it starts thinking that you're holding down one different key on the keyboard.  The annoying thing is that the keyboard works correctly at all other times.   The Machine: I'm using a Dell Latitude E5520.  This laptop is maybe about a year old.  As for what software is being used, I'll explain the details next.   What I've done: So, the first time I encountered this problem was was after installing encryption software on the laptop - I'm using TrueCrypt (http://www.truecrypt.org/) to encrypt the laptop harddrive with a standard windows XP install.  Truecrypt is pretty simple to use: you install it, give it a key and it encrypt the drive, and it'll load before the OS, prompting for a password - you type in the right password and it loads the OS.  With this computer though, I was unable to actually give it a key because the moment you pressed any key on the keyboard it acted like a key was being held down on the keyboard.   Now, the keyboard worked perfectly fine in the bios (which on this computer runs in it's own little gui), and if you pressed esc while in truecrypt (because a key had not yet been set) it would load XP, where the keyboard worked perfectly.  Additionally, it *seems* to work correctly when selecting a boot option - but if someone was holding down a random key on the keyboard at that point in time chances are good it wouldn't affect anything anyways.   So, I figured that it's probably a problem with the software - completely reformatted the hard drive and re-installed everything.  No luck.  I then figured that it might be a hardware issue, so I tried swapping out the keyboard (didn't work) and the motherboard (didn't work) and the memory (didn't work) and flashing the bios (didn't work.)  When none of that worked, I took the harddrive out of the computer, put it into an identical one, which has the exact same bios settings, and the keyboard worked correctly in truecrypt!  How's that for annoying?  Also, just as an FYI, I did run the dell diagnostic software on this machine, but there were no issues discovered.   After all of this, I decided on a whim to load lubuntu (https://help.ubuntu.com/community/Lubuntu/GetLubuntu) onto my flash drive and see if I might find something useful by booting off of it.  There, if I tried entering Command Line Interface (CTRL+ALT+F1 for example), immediately it would act like I was holding down the ~ on the keyboard.  I then loaded DOS onto my flashdrive, booted off of it again, and found the exact same thing, except once I pressed any key on the keyboard it would act like I was holding down the c key.   To throw another lovely wrench in the works, this problem only happens when using the laptop's integrated keyboard.  This will not happen if I use a USB keyboard instead.   In Summary: So, the keyboard acts like a specific, random key is being held down in any CLI - but not in any other interface - and after replacing all the hardware and software involved I still have absolutely no idea why.  If anyone can held me out with this I would be incredibly grateful.  Thanks!

KristianD · Accepted Answer

After disconnecting everything non-essential and slowly reconnecting it I found out what my problem was: the volume control on the laptop was faulty.  Looks like one of our users spilled something that dripped underneath the volume down key, shorting the circuit board and making it act like the volume-down button was being held down.  The CLI was interpreting this as input, hence the random key being held down thing.  Disconnecting the volume control cable works to solve the problem for now, and eventually I'll replace it.  Thanks for the input!

KristianD · Answer

That's a bit of a moot point, since the keyboard does the exact same thing when booting from both MSDOS and Ubuntu off of a USB stick. Also, this problem does not happen when the hard drive is plugged into an identical laptop.

It's probably worth noting that my company is using this exact same software combination across a dozen laptops of the same make and model in our organization, and this is the first time we've ever seen this.

Robin3 · Answer

Have you tried an external keyboard? Same issues?

Robin3 · Answer

When you re-installed the OS, did you try the keyboard BEFORE you installed any of your software first? If so was it working ok and at what point of your software installs did it start acting abnormally? .

KristianD · Answer

Bwah, shame on me for forgetting to mention that! This problem does not occur when using an external USB keyboard. It's only when you try and type on the integrated one that this happens.

Modified my original post to include that info.

Robin3 · Answer

Hmmm yes this is a bit odd isn't it. If the external keyboard works then one would assume laptop keyboard failure but you say it only occurs in CLI environment. If the laptop keyboard was faulty it surely would occur in all scenarios.

What about the Windows on-screen keyboard? Same issues?

I'm convinced this isnt a software conflict. How willing are you to wipe the drive completely and just load the Windows OS?

KristianD · Answer

...how exactly am I supposed to use the windows on-screen keyboard if I'm in a CLI?

And it's definitely not the software because I can pull out the harddrive, boot linux off of a USB stick and still have the exact same problem.

maxd · Answer

Interested to know why it would only affect in a non-gui mode ??

Robin3 · Answer

Me too! The idea behind the Windows On-Screen keyboard was again to eliminate hardware issues. I'd of thought the keyboard diagnostic would of found that straight away. Ahhh well at least you found the problem.

maxd · Answer

It appeared to me to be an encrytion/bios 'conflict' somewhat similar to this page:

https://kc.mcafee.com/corporate/index?page=content&id=KB73130&pmv=print

I realise it's a stretch but there are enough similarities... I was also going to ask him to rule out the second inadequacy in his truecrypt sw (since the 5520 is uefi-capable):

http://www.truecrypt.org/future

btw Paul, on my xp desktop there is a real conflict when attempting to run OSK and CLI; you ?

faizalenu · Answer

the reason that the CLI sees it as input is because volume control runs through the keyboard controller.  It is 'filtered' during GUI but not command line.....

JoeMoose76 · Answer

I have the exact same issue and you saved me time to troubleshoot the issue.   Thank You.:emotion-1:

Locked Topics – Laptops General

Was this post helpful?