There was a thread on this about a year ago, but the issue was never resolved. I have a buzz coming from my Eden WT300 (upgraded to WT400 specs) that I can hear through speakers and also without anything (except the power cable) plugged into the amp. It seems to come directly from the toroidal transformer. The previous thread suggested loosening the bolt holding the transformer down and rotating it, but I have tried this and it has made the buzz coming through the speakers unbearably loud! Is it time for a new transformer? I was told that they are rather costly... Thanks!