Hello, i am really annoyed by this quite high buzzing coming out of the speakers when i have my amp in phono-mode... I'd be so glad if you could point out what could be wrong. Equipment: Amplifier: Harman Kardon PM 660 integrated amp (1980's?) Record Player: Thorens TD166 MKII (1980s?) Blu-Ray player: Some new phillips Speakers: Infinity Primus 360 Facts: Buzzing is only annoyingly high when reciever/amp is in phono mode. Buzzing is dependant of volume control. Buzzing is constant even if the Record player has no power. Buzzing gets higher if i pull out the ground-wire coming from the record player to the amp, which is always connected. Buzzing disappears if i unplug the red/white(or black) cables from the blu-ray player to the reciever/amp. Buzzing is constant even if the blu-ray has no power. I already tried to take the power from another electricity-slot in another wall to the amp/receiver - no change. So, i bought a blu-ray player today and this is when the trouble began. Before, when i only had the record player connected to the amp/reciever there was only low buzzing that did not annoy me. Now when the blu-ray player is connected with the amp/receiver, the buzzing is annoyingly high, even shining through music playing on medium-low volume. I already have bought One ground isolator, this is it on ebay http://www.ebay.com/itm/280598056850?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 which i have tried before both the record player and blu-ray player, no change at all. Now, does anyone know what could be wrong, and/or what i could do? I have gotten 2 advices from people, but they were absolutely not certain - to buy more isolators and put them everywhere, and the other one said i should run another ground wire from the record player to the back of the blu-ray player. VERY thankful for advice... i can't live like this!