initially don't recall this problem. When audio is required .. whether video or music app started, a background annoying hiss that stays in background, like the tape hiss of yesteryear. if the say music player is paused or stopped the hiss continues for 8 seconds, then shuts off. awful feeling it's hardware related. tried cold boot, resets etc. no avail. have read some others same problem. Your suggestions would be appreciated. I'm not in home country so Apple stores aren't closeby (working in Thailand). what do you think about (groan) a full restore? cheers Merv.