Audio problem with my computer

[bluaki]

For the line-in port of my computer, the sound doesn't exactly come in right.
Just sticking a plug in there will make it get only the right sound while the left is just muted or whatever. Wiggling the plug around in certain ways will make it switch to left. At some very hard-to-keep position, both left and right seem to work flawlessly, though even tape seems unable to hold a cord like that for over 10 seconds.

I just want to record from line-in as stereo sound. I don't have a sound card, the port is just attached to the motherboard. Do I need to buy a sound card or is there some way to fix the port that's already on the motherboard?
...are there any cheap sound cards (PCI) that you know of or any USB thing that can work as one? I don't care for surround sound, just stereo. I also don't care if the input is TRS or RCA.

Oh yeah, the port is like right next to the fan if that affects anything
I've tried blowing in it with a hairdryer that had the heat turned off and that didn't solve anything.

[Zeta]

Sounds like a connection inside has gone bad.

If you can open up your computer and have free PCI slots, it's not hard to install a sound card.

http://www.newegg.com/Product/Product.aspx?Item=N82E16829102003-- Here's one that will work.

[bluaki]

Sounds like a connection inside has gone bad.

If you can open up your computer and have free PCI slots, it's not hard to install a sound card.

http://www.newegg.com/Product/Product.aspx?Item=N82E16829102003 Here's one that will work.

Okay, I'll order that in a few days. I have two PCI slots open, I'll use one for that and the other for a graphics card later on.
Also, you accidentally added two hyphens at the end of the URL

Is there any difference between using the line-out off the sound card in comparison to the motherboard?

[Zeta]

Other than the problems with your motherboard, no.

[The artist formally known]

I reinstall my sound card if something happens to my audio. Sometimes it fixes it.

also ur post was tl;dr

[bluaki]

I reinstall my sound card if something happens to my audio. Sometimes it fixes it.

also ur post was tl;dr

I know it's not a driver problem because it changes as a wiggle the plug.