If you go to DSP Studio, you will see a tick box in the lower left corner.
It says either clip protection or flat line over flows.
I noticed my jriver doing that as well, and I narrowed it down to sudden bursts and the clipprotection was stopping that and the sound would stop until next song or whatever.
Try setting to flat line over flow. You will likely hear a lot of distortion. ramp down the preamp in the equalizer.