Re: Loud humming through amp when USB is attached.

support@line6.com — Sat, 12 Jan 2013 21:12:02 GMT

I have a very similar problem. I don't have a lap top, but a desk top Mac. The noise goes away as soon as I disconnect the POD from the USB cable.

POD HD500 NOISE-A SIMPLE SOLUTION TO A BIG PROBLEM (and a follow-up question)

support@line6.com — Sat, 12 Jan 2013 20:48:55 GMT

Here's the meat and potatoes of what I'm here to share/ask:

THE GOOD NEWS: WHAT I CAN TELL YOU THAT WORKED AND THAT MIGHT HELP OTHERS:

I had a TERRIBLE noise* problem with my POD HD500. I discovered it was the halogen lamp** connected to the same power strip that I had the POD plugged into. As soon as I moved the lamp to a line not shared*** by the POD, the problem was solved. Sort of.

I'll explain the "sort of" caveat in a bit. It was brought to my attention that halogen lamps are NOTORIOUSLY noisy, especially if plugged into the same power strip as the POD. So that's the good news. Get rid of the lamp, get rid of the annoying buzz. But I'm not out of the woods yet.

THE BAD NEWS: I STILL HAVE A PROBLEM:

When I discovered the "Halogen Lamp Solution" I had UNPLUGGED my POD from the USB hook up to my Mac. As soon as I hooked the POD back to the computer the noise came back. So far as I can tell, the noise is identical to and just as bad as the one caused by the halogen lamp. I thought, "Maybe it's that stupid lamp again." So I unplugged the lamp and that didn't help in the slightest.

So, bottom line, I've figured out PART of the problem, but now I've apparently got some sort of interference or ground loop issue having something to do with my computer or something sharing the line (or around the line) my computer's plugged into.

Now that I know it's not the POD's "fault" does anyone have anything to add to this discussion to help me trouble shoot the noise that APPARENTLY is associated with being hooked up to my Mac?

Thanks, everyone!

OTHER HELPFUL INFO:

My wife was helping me research this problem and found a forum on Harmony-Central where a POD HD500 user said he/she plugged their POD directly into the wall outlet and the noise was gone. I tried that (on an outlet at the opposite side of the room) and the noise problem totally went away. The main helpful thing about this discovery is that I was able to rule out there being a problem with the POD itself. I'd spent about 90 minutes reading Line 6 forums and came across all sorts of more complicated solutions involving the POD as the main cluprit. So this was a huge breakthrough. I tried to log on to that Harmony-Central forum to thank them for the post but I don't have the right permissions to do so.

OTHER INFO ABOUT HOW I DID MY INITIAL TROUBLE SHOOTING:

The noise has nothing to do with the patches/presets or amp sounds or noise gates, etc. I knew this because even the quietest of patches are associated with this annoying hum. I tested the amp I was using to monitor the POD along with my guitars and patch cords and was totally able to pin point the noise as coming from the POD. Even if I had the volume and master knobs on the POD all the way down as well as the volume knob on the guitar all the way down, the terrible hum was still there in full force.

I could say more but chances are no one's reading this far anyway . . .

*The noise is a "buzz/hum" as opposed to a "shhh/hiss" problem. I'm not much of an electronics whiz by any stretch of the imagination, but from what I understand it was a 60Hz buzz or however you describe it.

**About an hour after I discovered the solution of moving the halogen lamp to an adjacent power strip (before plugging the POD back into the computer) I remembered how over 20 years ago I had a terrible buzzing connected to my guitar rig that plagued me for weeks. It turned out I had a heating pad on that was apparently kicked under my bed that was causing the interference. Duh. Lucky I didn't burn my parent's house down. Too bad I didn't remember this story earlier. It would have saved me a couple hours of research and problem solving.

***The power strip I had the POD plugged into was being shared with the halogen lamp and a couple other AC adptors not currently in use, but there for when I needed them for their respective devices. I moved the halogen lamp to an adjacent power strip and the noise was gone. The adjacent power strip I moved the haologen lamp plug to is connected to the same wall outlet from the same outlet as the one connected to the POD. I mention this only to illustrate some details about how much a nearby halogen lamp can or cannot affect your rig.

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Re: Loud humming through amp when USB is attached.

POD HD500 NOISE-A SIMPLE SOLUTION TO A BIG PROBLEM (and a follow-up question)