Sometimes, only the f,g,h,j,k keys do not type

[YaSo]

Starting about a month ago, I had this recurring problem where only a few keys would not enter a letter when typing. It's only (I think) the F, G, H, J, K keys. Sometimes it goes away, sometimes it stays until I reboot.

At first I thought it was related to some fishy sites I browsed in Portable Firefox using SandboxIE. When I terminated all programs in SandboxIE, I would get control of those keys after a few minutes.

Today when I booted up my PC, I had this occur right from the beginning. I ran scans in MS Security Essentials (don't laugh, please) and MalwareBytes. Nothing bad came up, so after a reboot, all seemed fine.

Odd Thing #1: Two hours later, after I had been browsing 'normal sites' in Chrome only (No SandboxIE, just normal Google, TomsHardware, Youtube, Amazon) I found it happened again.

I decided to play a movie on a second monitor while trying things out.

Odd Thing #2: Microsoft's On-Screen Keyboard does NOT register those keys (letter K for example) as a typed letter in an explorer window, browser, or start menu search.
Odd Thing #3: VLC recognized me clicking madly at the K button as setting the audio delay ahead on the movie!
Odd Thing #4: When I closed VLC, the problem stopped.

The problem did not come back when I played the movie in MPC-HC.


I don't think it's due to maxing my older system. This happened before I started playing Fallout 4 at 1080p medium settings. VLC plus some Chrome tabs only used 15% CPU / 3.8gb of 16gb. MPC-HC only used 9% CPU.

No hardware changes were made in the last several months aside from a gaming mouse in August. I am using a 5 year old MS X6 gaming keyboard and I tried an even older Acer OEM keyboard (both USB) and neither keyboard would type F, G, H, J, K keys.

I have a quad-core I5-750, 16gb DDR3, and an SSD for Windows, programs and games.

Help? Thanks in advance!

 

[D3LL]

Sounds like a strange one!
Are you all up to date with your Windows Updates as it sounds like a keyboard controller driver issue. However have you also tried using another USB port to be safe.

 

[Barman58]

Have you got access to another hardware keyboard - I used to see this in businesses in the good old days when all keyboards were switched type.

The keyboards are wired in a matrix arrangement and this sort of issue was due to mechanical failure of the supply to a bank of keys. as you say that you have a gaming keyboard this would normally use a similar system and you could have a damaged connection in the keyboard. I have physically repaired this type of error in the past when I had a failure on site where no replacements were available - but these days if this is the issue you have a replacement would b the best solution

 

[YaSo]

All but a few optional updates are up to date. Microsoft got out of the Sidewinder gaming keyboard market a while back but they do update drivers every so often, last one was in August.

I've tried front panel USB, rear panel USB, an add-on USB3 card port, powered USB hubs connected to the rear panel (which is what I had them on for 4 years), all no difference until I close a program (VLC, Chrome) that fixes it.

I've tried a basic wired $30 Logitech USB multimedia keyboard, and a few pack-in USB keyboards (Acer, Gateway) and all exhibit the same symptoms. All keyboards were at least 4 years old.

Baffles me too folks.