Often an AC adaptor on the same circuit will generate that anoying 60 cycle hum on audio recordings. It’s often the speaker adaptor, so if your speaker adaptor or cell phone or whatever is plugged into the same circcuit as the computer, try unplugging them for recording .wav/.mp3s. If you need to monitor the sound try headpones in the speaker jack. That’s the first thing I would try as it’s a common problem. Some power strips/conditioners have filters that solve the problem. If that’s not the problem, the line noise could also be an audio cable short or more likely a bad ground or sheilding somewhere - try unplugging the speaker audio cable and/or the audio cable from the CD/DVD to the sound card.
Eliminating those simple things first will either fix it or point to something else as the cause.
BTW, I’ve been using Winamp at least a decade. I’ve tried more than a dozen players, but I always go back to Winamp. The new auto-tagging feature sure helped weed out a lot of music from p2p sites labeled as Dr. Hook that really wasn’t.
So......Drumbo KNOWS about his stuff, trust me. :)