Community: Message List - Loud humming through amp when USB is attached.

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.

Re: Loud humming through amp when USB is attached.

support@line6.com — Mon, 16 Nov 2009 22:38:05 GMT

Just wanted to report that I am also experiencing the humming problem. I can experience it even without a computer attached, or anything else connected to a power supply. I have reduced the setup to the following:

- Connect a cable between the output of my M-Audio ProFire 610 and the guitar input (or aux input) of my X3

- The ProFire is not connected to anything else. No power cable, no firewire, no nothing. Not that it matters, but the power switch is also turned off.

- At this point there is no hum

- Touch the grounding of a firewire cable connected to the ProFire and the grounding of a USB cable connected to the X3. Now a clear, not very loud, but annoying enough, hum is heard.

Note that the only thing connected to a power outlet is the X3.

Disabling the input where the audio cable is attached (guitar/aux) removes the hum.

I'd be happy to find a solution to this humming problem (without spending a lot of money).

Message was edited by bjanders: Changed "this problem" to "the humming problem", so that is not confused with the other problems discussed in this thread.

Re: Loud humming through amp when USB is attached.

support@line6.com — Wed, 14 Oct 2009 02:03:04 GMT

That is not normal at all, You might want to have that thing looked at. Or at the least, try doing a system reset and see if it fixes it.

Re: Loud humming through amp when USB is attached.

support@line6.com — Tue, 13 Oct 2009 23:40:57 GMT

possibly you have the outputs muted... but i've never heard of this one.

Re: Loud humming through amp when USB is attached.

support@line6.com — Tue, 13 Oct 2009 23:40:11 GMT

doesn't work that way on mine... headphones and 1/4" active all the time

Re: Loud humming through amp when USB is attached.

support@line6.com — Tue, 13 Oct 2009 23:25:44 GMT

anyone else have this problem?

Re: Loud humming through amp when USB is attached.

support@line6.com — Mon, 12 Oct 2009 01:13:13 GMT

I usually leave my headphones attached at all times even when I play through the amp. I disconnect the headphones and I still cannot get sound through the amp.

Re: Loud humming through amp when USB is attached.

support@line6.com — Thu, 08 Oct 2009 14:04:27 GMT

When you plug something into the headphone jack, it bypasses the 1/4 inch out jacks.

Re: Loud humming through amp when USB is attached.

support@line6.com — Thu, 08 Oct 2009 08:44:15 GMT

So I unplugged the power source of my computer ( I have a laptop) and the hum is gone. Now the only problem is I don't hear any playback from the computer when I attempt to play back something I recorded. I am confused I can here it through the headphones, but it doesn't transmit to the amp.

Re: Loud humming through amp when USB is attached.

support@line6.com — Thu, 08 Oct 2009 02:23:24 GMT

A USB Isolator works as a hub. The x3 does not work through hubs due to the bandwidth needed. It would also not get rid of any ground loop if you were to need to use the headphone jack to send sound to a board for instance. For USB connections they work fine. There are better options for getting rid of ground loops.