The computer is getting a humming or buzzing noise

Often, this is the result of a poor wire connection to the sound card, although it can also result from a lot of electromagnetic interference being pumped out by a poorly shielded component within the system, especially the power supply. Unplug and replug all internal and external wire connections to the sound card, making sure that each is firmly seated. Also make sure that in your sound mixer software (in Windows double-click the speaker icon in your System Tray) you have the CD volume slider set to maximum and the Master /Play Control slider at a lower level. Be sure to mute any devices not in use. As for buzz from poor shielding, this is a harder item to fix as finding the culprit often involves swapping out suspect parts. You can try unscrewing the power supply from the case without unplugging any wires and let it run outside the chassis to increase its distance from the sound card, but this can be a more involved operation than many beginners are willing to undertake.