So here's the problem:
You’ve got your guitar plugged in. You’re not playing it and there’s a noise. A hum. It’s not terribly pleasant.
Thing is, you touch the strings and it’s gone.
The response: It's ok. It's not a problem. That’s all as it should be. Guitars pick up interference and that comes out the amp as a hum. When you touch the strings, it's supposed to get quieter.