I've been lurking in the recording.org forums for quite some time now soaking up all the great info everyone has to offer. Now I hope I can get some of the same help!

I have recently hooked up the S/PDIF digital output of my Numark TTX1 turntable to the digital input of my Auiophile 192, but there's a problem. I have a constant noise at around 20 hz and below at -30 dB or so, which causes a DC offset in my recording. Of course, I can use a high pass to roll of this subsonic noise, but that's not really a solution.

What's causing this?

I tried 2 different turntables. I tried selecting different samplerates in the MAudio control panel. I haven't tried another audio input (I don't have one), nor have I tried a different cable.

Here's a screenshot of the input level monitor, the recording, and a frequency analysis.

Thanks in advance for any help!