[SalB]

Hello,

I've had my wonderful Yamaha APX-7A for a year or so .

Just very recently its developed a hum (ground loop somewhere) .

We've tried three different cables as well as different channels on the mixer, and even mics and other instruments using the same cables and mixer inputs. And we have changed batteries in the guitar. But its only the APX-7A that makes the hum.

We are pretty sure now its the guitar which is the source of the hum .

One factor worth mentioning is that we live in the wet tropics of northern Australia and it is now smack bang in the middle of the monsoon season- aka very warm and humid- although it seems to have forgotten to rain these last few weeks .

A friend lives on the Great Dividing Range about 1000m elevation. She says that when she comes from her cooler drier home down to our warmer more humid coast to perform that her Martin hums.

Is anyone aware of humidity creating ground loop issues with electric acoustics? Does anyone have a suitable fix if this is to be our issue too?

Thanks for your help and attention

cheers ... Sal