Found a rather strange problem while messing around with the free demo of Neat Image 5.3 while listing to some music with fb2k. The steps required to reproduce the problem:

First, download the 2.1 meg Neat Image demo from http://www.neatimage.com/ (it's a nifty image noise reduction program)

Make sure FB2K isn't playing anything if it is loaded.

Run Neat Image, hit the "Open input image" and load an photo or other image that's got sky or another relatively undetailed area. Even a blank .bmp saved from MSPaint will do fine, it's just to give the next step a chance to work.

Select the "Device Noise Profile" tab, and hit the "Auto Profile" button. Normally, a blue rectangle showing the area being analyzed, a small progress bar next to the auto profile button, and a percent complete message in the menu bar will immediately appear and show the program "doing it's thing."

Now, start some music up in FB2K, load an image in Neat Image again (can be the same one) and try to Auto Profile again. On my system it appears to lock up for a moment, then suddenly jump to showing the process complete. Do it enough times (I was comparing noise between different models of cameras at the time when I first found the bug) and Neat Image will lock up completely.

Tried it at work on a Win2k machine that has some kind of AC'97 soundcard (probably integrated into the mobo) and the problem didn't happen. I'm running XP Pro SP2 at home with a SB X-Fi.

Did you try using another media player? Eg. Winamp? What output plugin are you using? What version of foobar?
Maybe the directsound buffers interfere. it happens. Just don't use both software at the same time, or report the problem to neatimage -- they don't plan on their software being used at the same time as games (which usually are the ones who create these buffers)

FB2K v0.9.1. Doesn't happen with WMP or Media Player Classic. Doesn't happen with ASIO or null output, does with directsound or kernel streaming.

I'll email Neat Image support and see if they have any ideas. Neat Image doesn't use sound at all, which is why I'm a bit confused by this one.

It looks to be some kind of multitasking conflict: if I set the playback thread priority to minimum in fb2k Neat Image will work correctly while fb2k's audio stops after the buffer dries up. If I set the output buffer to 8 seconds it'll continue playing as it takes Neat Image less than 8 seconds to do the auto profile. I don't understand why it should be a problem, fb2k uses an almost unmeasurably small amount of processor time when playing an MP3 but the problem still happens if the playback thread priority is set to anything above the absolute minimum. I suspect the problem isn't with fb2k, I even tried playing Oblivion with it running in the background without any problems.