I have problem with a Focus FK-555 keyboard, which I was hoping someone could help me with.
I use this keyboard on a near native PS2 port (HP laptop docking station), and a Gigaware PS2-USB adapter. The underlying problem is the same, but the consequences are different depending which method I am connecting to.
It has random keys that repeat, although they most commonly occur on the A, S, and D keys, since they are used the most. I have seen the problem on C, and backspace keys too.
On the near native PS2 port, the problem goes away for the most part if I lower the repeat and delay functions in windows keyboard settings. However, on the USB-PS2 adapter, problem persists, and mimics stuck keys. Eventually the keyboard locks up and needs to be unplugged and plugged back in. It also flickers off the keyboard lights when this happens.
I don't think it is the ALPS switches themselves are the problem in light of the above. I am inclined to think there is something wrong with the keyboard matrix, data line, keyboard controller. I suppose there could be something wrong with the keyboard cable itself but I don't have any spares (I was thinking of picking up a soarers internal keyboard converter for that purpose).
Does anyone have any ideas what could be happening, and how I could potentially go about diagnosing this? I have a digital multimeter. No access to more fancy stuff such as logic analyzer or oscilloscope (not that it would help, have limited proficiency in electronics). Alternatively, if anyone knows of a shop, or even better yet, one in the Dallas Fort Worth, TX area, that'd be even better.