HELP USB to DAC = Loud Bursts of Volume


Okay, I have a Macbook Pro and a Bel Canto Dac 3. I have gotten intermittent loud bursts of volume when I am connected via USB. This has happened 3 times at least in the last month. The volume setting on my Dac/Pre has not budged and I have no idea what is causing this. It just all of sudden goes to like MAX volume. I quickly turn the amp off or unplug the usb to avoid damage to my speakers.

I have never had this problem when I stream wirelessly from Airport Express to the Bel Canto's optical input.

Anyone have any idea what is going on? I called Bel Canto and they have never heard of such.

HELP
restless_times
It has only happened when connected via USB and while music was playing. Once you mentioned static a light went off. I am sure that at least two of the times this has happened, it was as I touched the MB Pro, and I distinctly remember static electricity. I immediately killed the music because I was concerned for my speakers.

It makes perfect sense to me now, because before I upgraded to the Pro, I had a Macbook for a few weeks. The issue never happened as the Macbook uses plastic casing.

I will call Bel Canto again tomorrow and ask for Matt and I will make sure to mention that I am not the only one having this problem. Hopefully they can resolve this issue. I have resulted to using the Airport Express again, not that it sounds bad, but I prefer the USB set-up since the general consensus is that is sounds better than using the AE.
A follow-up to my previous post, which is awaiting approval ...

This sudden volume 'up' has nothing to do with which tracks
happen to be playing, or wireless, or anything else, I'm 99% sure.
It's happened to me at least a half-dozen times, and only at
moments when I've touched the MacBook Pro, while music
is playing.

I do think it might have something to do with the MacBook Pro's
aluminum casing, and a build-up of static electricity. But that's
only my best guess at the moment.

It really is the darndest, and strangest, and scariest thing.

Tweeters still intact, so far,

Michaelct
Guys - if Bel Canto fails to provide satisfaction, you might consider trying the Opticis USB cable. This is a fibre optic cable that lives between the USB output and the USB input. Net effect is that it provides complete electrical isolation between the computer and the DAC - meaning that it might be a way around your static issues.

I would be pleasantly surprised if Apple acknowledged this problem, but some of the Mac tech sites might have some coverage.
Ckorody -- thanks for the tip.

I think both of us plan to move to Mac Minis in the near
future though, which, given the circa $200 price tag
for the USB-to-optical-and-back-again cables,
probably makes the most sense, all things considered.
But thanks again for the tip.