I have an XMC 1. When I play back stereo CD's I often set up surround sound simulation. On one album, using the PLXIII simulator, I get sound only from the rear speakers. Stereo and Balanced in work fine. Other simulators seem to work fine. It's not happened on any other album. This one is an Enlightenment Sonny Rollins set. It is as best I can tell an EU Public Domain production. Any ideas on what's going on?