Please Help!!!

Hi,
I Recently Purchased A Zebronics Zeb-sw13100r 5.1 Speakers.
But Suddenly While Playing A Movie Or Any Game The Sound Becomes Really Low And Sometimes The Dialogues Or The Background Music Just Disappers.
But If I Keep Switching The Speakers On And Off It Suddenly Becomes Ok(the Sound Is Proper)!!!
Now All My 5 Speakers Are Connected To The Subwoofer...
And The Subwoofer Is Connected To The Pc.
Now,i Have Plugged In My Other 2 Stereo Speakers And They Dont Pose A Problem...so Now Iam Confused!!!

Please What Is The Problem???
Thanks,
Ysk.

You might want to rethink how you hooked everything together - have you followed the instructions in the manuals?

Zebronics?

yes everything has been connected acording to the manual...thats for sure!!!
and yes its zebronics-company which manufactures gpu,speakers and cabinets.