Ok, I'm about at my wits end. I have a noise problem I can't figure out. Essentially the problem is a popping sound emitted from the front left and right and back surround speakers when the pre
amp is decoding and outputing the signal to the
amps. The problem started when I purchased a N.O.S. Harman Kardon Citation 5.1 to run my surrounds. I already had an Emotiva XPA3 running the front left, right, and center. I never noticed the popping in the front left and right when the Emotiva was running them, but I purchased a N.O.S. Citation 7.1 which I bridged to the left and right. I was using the amp in my receiver to run the center until I more recently got a Emotiva XPA 100 to run the center.
The popping sound is like using a 9 volt battery to test speaker polarity. It occurs also if the amps are already on before the receiver has finished it's start up. The receiver is an Onkyo TX NR809, which is just acting as a pre/pro. The rest of the setup includes a Directv digital box, Xbox 360, Oppo BDP 103, and a Panamax M5300PM as the surge suppressor/line conditioner. All the pieces are using HDMI from the Onkyo to the unit and then using the Onkyo analog outputs to feed the amps. I have done a ton of troubleshooting and have figured some things out. I figured it was the Onkyo at fault and sent it to their authorized repair center who told me they couldn't replicate my problem. After I sent the Onkyo to them I hooked up the Oppo to use it as a pre/pro while the Onkyo was gone and noticed it did the same thing!
The Directv box would cause the pop anytime I changed the channel or muted, basically anytime the sound was processed. I fiddled around with it and turned off the Dolby Digital output and let it just output PCM. That stopped all popping except for muting and unmuting, and the shutdown or turn on where the Onkyo shut down before the amps. When the Onkyo is only getting the PCM signal it doesn't have to decode the signal because it is using the preset decoding option I chose. The Xbox will cause the pop under the same situations. Also ditto for the Oppo.
I spent a good deal of time to route the power cables away as much as I could from the HDMI and RCA cables as well. The outlets being used check out ok and show good ground as the Panamax shows "wiring ok" as well. I have tried switching HDMI cables and RCA cables with no changes. I use the high end Monster and Blue Jeans/Belden HDMI cables as well as RCA. I even tried shielded RCAs I had lying around that I used for car audio, no change. I swapped the Citation amps to run the surrounds and no change. I hooked up the Emotiva on the fronts again, but noticed when my ears were right next to the towers that the pop was there with the Emotiva, but I was only able to hear it with my ears right by the speaker. That is probably why I didn't notice it before. I am so frustrated and at my wits end. I tried explaining to the tech where I sent the Onkyo to, but he had no idea what the problem is and just said he couldn't duplicate the problem. HELP ME PLEASE