We just moved into a 60 year old house and discovered that my daughter's
electric guitar and amplifier won't work properly. There'a a loud hum
coming from the amplifier. It stops when she puts her hands over the
strings, but starts up as soon as she removes her hands. Could this be a
grounding problem? Any suggestions? (There's nothing wrong with the guitar
or the amplifier. She also has a bass guitar and a bass amplifier and the
same problem is occuring with them too). Thanks.