Noise in G5 audio line out

[fosters005]

Hi,
I have a G5 twin processor which I bought just before the Intel chip model. It has all sorts of hum and noise in the audio line out when connected to my larger home music system. I have Applecare and the Apple Store tells me that they need to replace the motherboard. I'm awaiting that part to come in now. However, it sounds to me more like old fashioned transformer hum and I'm wondering if anyone else has had this vexing problem -- and if so, how it was finally resolved? I'm too old to keep hauling the heavy unit around much more. Thanks for your time!

 

[Sun Baked]

Don't they even read their own support site, look up ground loop on Apple's support site.

You'll find...

Macintosh: Solutions for noise in the audio signal

 

[fosters005]

Don't they even read their own support site, look up ground loop on Apple's support site.

You'll find...

Macintosh: Solutions for noise in the audio signal

Thanks for this; good to know re the Mac web page. I've actually done all of that including the line transformer -- and the hum persists. At 65, I know from ground loops and should have called it that in my post. The interesting part of this is, several Mac laptops with Itunes that my friends have plugged in do not have the ground loop. Their sound outputs are noise-free as I naively expected the G5 to be. I'm going along with the "Genius" folks and letting them replace my motherboard this week. I'm curious about what they might try next and will let you know. Thanks again for your kind response.