Hum is usually caused by having different grounds.
You might try plugging the computer into the same outlet with your audio equipment.
Another common culprit is CATV cable. Try disconnecting your incoming cable TV connection while using the computer. If that's the problem, you may need to get a cable isolation device.
You might try plugging the computer into the same outlet with your audio equipment.
Another common culprit is CATV cable. Try disconnecting your incoming cable TV connection while using the computer. If that's the problem, you may need to get a cable isolation device.