Logitech Z506 - rear speakers produce low quality, distorted sound

As the title suggests, I am having trouble with the quality of sound on my rear speakers for this set. The issues doesn't spread to any other speakers - just the rears.

They distort certain kinds of music under almost any volume to sound like a 240p video recorder with a phone from 2003 - if that makes any sense :3


Now, I now this is a very cheap set and I shouldn't expect audiophile quality - especially on my budget - but it just doesn't seem natural. whenever I turn around to listen to them directly, the sound is distorted.


I'm using onboard sound from my Z77 Extreme-4m motherboard.

Is that an issue with my onboard hardware not being up to the job or the speakers themselves?


I'm here asking this question because:
a) I don't know much about speakers and sound systems
b) Google doesn't come up with anything remotely relevant to my issue

I would appreciate some guidance as to how I can diagnose what the real issue is - or what I could/would need to buy or upgrade to fix this.

Thanks,
Jake

If you're listening to music in a virtual surround mode, the rear speakers are always gonna sound garbled as hell. That is just a bi-product of the virtual surround slicing bits and pieces of garbled sound off of the 2 stereo channels and mashing them together to make a rear sound.

It's always gonna sound bad for music. Use stereo mode instead.