Recently I acquired DVD player (Pioneer) and enjoyed truly Dolby Surround using my Phillips - ESI Enhanced Prologic Receiver. However I noticed that there's hissing sound coming from the Surround speakers everytime I played DVD movies. My speakers are all Phillips (including surround). By the way i'm using ordinary copper wire connection which I think could be the culprit. Do I have defective surround speakers? Will appreciate your help and advice. Thank you.