Help please! USB DAC issues with "white noise"

[Paul Held]

All, thanks for reading this. I need some hardcore technical help/ideas to solve an issue. I've found the other thread here on the site which appears related to the issue I'm having with a system I'm configuring as a present.

 

My brother in law and I gave our other brother in law a fully baked server system for his 40th birthday. I've been doing this stuff for a number of years (currently on Mac gear but cut my teeth on XP and Vista for years before that).

 

In short, I gave him an almost-new Acer Vista (32bit, home premium) based pc with iTunes and a large ALAC library preconfigured on the pc's internal HD (we share musical taste, so I was able to give him ALAC of everything he already owned as I own it on CD as well). I did the legwork. My other BIL bought the new DAC, a Fubar USB DAC that some of you would know and may love (with the upgraded power supply).

 

That particilar Vista PC was surplus at my place, so I repurposed it as the gift server. I had never been doing much of anything, and had certainly never been used running music server. As such, it had not been really tested; I had no reason to think it wouldn't be fine... but nonetheless.

 

The complete config is this Acer Vista 32 PC running iTunes 9+, ALAC (mostly) library on the internal HD, Fubar DAC with ps upgrade, analog out to his audio gear (preamp, amp, etc.). I stripped off pretty much everything not focused on making music or basic web surfing related. It is wireless and running Avast AV software.

 

Here is what's happening. After a period of time, sometimes 20 minutes, sometimes all afternoon, the system will dissolve into "white noise". Itunes is still playing but all you hear is something that sounds like white noise. Stopping and starting the song sometimes cleans it up, but not always. Usually, he has to either quit and restart iTunes or off/on the DAC to get the system "rebooted" musically.

 

I took over my Keces USB DAC as a control, and the same thing happened, so it's not the Fubar (at least, not on it's own).

 

When I went over to have a look, I approached it from a Vista perspective and disabled all other audio options (analog, Realtek digital onboard, windows sounds, etc.), set it to Windows Audio System, altered/disabled power down options, etc. - everything I could think off. It's still happening.

 

Folks - any ideas that could help us solve this mystery? Many thanks in advance, Paul

 

[The Computer Audiophile]

Hi Paul - Wow you have a good one on your hands. A couple things come to mind.

 

1. If this happens after 20 minutes or sometimes after all day listening, is there something that runs every 12 hours or once per day on the machine? Indexing service or something similar?

 

2. Are there certain files that the system chokes on? Try running a playlist of a control group of tracks you know work perfect. Set it on repeat and let it go.

 

Another idea that just came to mind is create another user on the computer, which will create a new user profile, and try everything.

 

[Paul Held]

Thanks for the initial thoughts Chris - we can't find a pattern yet but that doesn't mean that there isn't one behind it.

 

We'll attack it as you suggested.

 

Anyone else with thoughts on this one? It looks like it's the DAC not the pc, but open to all suggestions. Thanks