Computer shutdown problem: caused by dodgy microphone?

Factual Questions
1

My Windows XP PC suddenly started shutting down without warning after a few minutes of use. Or even non-use - just sitting doing nothing and it would still click off. I even unplugged the hard drive, and as it sat with a blinking cursor, click.

Luckily I have a second PC, so I have spent the last few weeks swapping over to it, installing apps and plugging in all my peripherals etc. It’s not bad, but I prefer my other machine, as it’s quieter and faster.

But the last peripheral I finally swapped over was my microphone. It was cheap as chips, it plugs into my soundblaster with a 3.5mm plug, so it’s not the greatest piece of machinery ever. But now when I go back to my original PC to swap files or whatever, it no longer shuts down, as least as far as I can tell from my experimentation.

It doesn’t make a lot of sense to me, but then the whole situation is mystifying really.

Is it possible that the cheap microphone could have caused those shutdowns?

2

In theory, any short can shut down a computer, and any conductive material can cause a short. But I would expect the plug to be loose and something metal to be touching the soundcard if this were the case. Or the soundcard itself could be bad, and is causing the short.

An experiment would be to plug up something else to the microphone port, and see if you get the same problems. You don’t mention the microphone causing a problem on the other computer (which makes sense if what I said above is true), so it is unlikely causing the problem by itself.

3

Good point. I’ll experiment with some cables and see what happens. The soundcard itself, or that socket at least, does sound more likely, now that you mention it.

4

And you were right. I put an unattached cable into the mic socket, and five minutes later it shut off again.

It’s definitely the mic port.