Over modulating buzzing at low end frequencies

I get this buzzing on my speakers and headphones when I play bass instruments like Kick and Snare Rock. I've tried playing with the individual volumes and the master volume, but I still get a buzzing. (It's the same type of over modulated buzzing from HP Arena speakers that Sarah Brightman got at a 2000 concert she did in San Jose, CA.) Hydrogen treble instruments are fine. What am I missing? How do I stop the buzzing?

I have version 0.9.3 in OpenSUSE 11.4 x86_64. I believe I have a beta version of Hydrogen in OpenSUSE 12.1 x86_64 which is also having problems with buzzing overmodulating at the low end. When I used Hydrogen in OSS 11.3 i586 32 bit, I had no such problem. Hydrogen sounded beautifully through and through.

Thanks in advance!