Hi Johan. Welcome to Beoworld.
I have the same problem, but I have a BV3. I can't play estereo sound, for exemple a CD, click of XMB,...
I did a test: I tried a digital coaxial with other dvd player, without optical-coaxial converter. I put a CD into, and i got the same problem: No sound. However, i can only get DTS and DD to work. That was the ultimate test. The surround module is the problem, which doesn't allowe play pcm stereo through digital coaxial.
I just called B&O.