I exchanged it, but the same problem remains. Clerks at the store didn't know what could be the problem.
Anyway, my girlfriend told me that she had a similar problem with her micro Hi-Fi system: she couldn't hear the lead guitar intro on just one track (a completely different one from the one with which I'm having trouble), while the other notes were clearly audible. When she played the disc on another system, there were no problems.
If you can think of some website or place where I could look for the answer I would greatly appreciate it. Although the problem is not huge it is very frustrating to me.