Youra6 what is the sensitivity of your speakers? It's possible the speakers you own are far more sensitive than the reviewers speakers, hence the hiss. Note that with preamps that haven't any mute relay, when they initially power up, it's a good idea to turn the preamp on first, wait a minute then turn the amp on. When shutting off the system, shut the amp off first then the preamp. So, the preamp is first on last off. Hope that helps. I would contact Cary to make sure this is normal..