Water on Motherboard Effecting Headphone Jack Audio

I have a self built computer, and recently a small amount of water was spilled through the top of the computer and onto parts of the motherboard. I immediately powered off the computer and set to drying off the parts inside. After getting all i could see, i put it back together. Everything worked perfectly fine, but now, about 7 hours later, the audio to my right ear is quiet compared to my left. First thing I checked was the headphones, they worked fine on another device and other headphones plugged in had the same problem. I took a look at the motherboard audio connector and three or four pins seem to have some kind of corrosion on them, as well as the connector. So i decided to test the motherboard audio output directly, with both the case connector connected and disconnected, each yielded the same result. Is there any way i can clean the audio connectors or something on the motherboard to fix the issue? Or if that doesn't work, could i buy a pci sound card and throw that in there and fix the audio problem?

Thanks