So, today I returned it and took a new one home. Just got it set up, and upon testing I was happily greeted with the same issue.
Have I just bumped into a faulty line of Logitech's X-530's or is it because instead of a sound card, I use my motherboard's integrated one. I have Abit's IC7-motherboard and it's compatible with 6 speakers, and 5.1. And I don't quite understad how IC7 could cause the problem to exist in the way it does and therefore don't really think that buying a soundcard woul help.
Anyone else had a issue like this with X-530? It's a rather lenghty journey to the store where I bought it, and not even sure if I want to try a new one anymore.