I have an Onkyo NR 3007 and currently a 4.0 speaker setup. I did run several audyssey setups but I do always get a scratching noise on my right front channel. I can attenuate the noise by setting the audyssey reference level to 15db, but this will not eliminate the noise completely. Onkyo support could not discover anything unusal with my device. I get this noise whenever audyssey processing is engaged.
Now the funny thing: As soon as I enable the subwoofer in my speaker settings the noise is gone! I don't hava any sub attached. I don't know what influence this will have on audyssey processing but did someone observe some similar effect?