I did call and speak to Scott earlier today, and I will be calling him tomorrow with an update, but I am looking for any other suggestions out there;

I have the 7700 amp that I had connected with an Onkyo PR-SC886 via XLT connectors. Today I swapped out the 886 with a Marantz AV7005. Everything was turned off and unplugged. I made all the connections, did the set up and everything was fine.

I ran Audesssey and at some point between it finishing/calculating-the command on screen to unplug the mic-and unplugging the mic, the dreaded ground loop noise appears in all speakers except the subwoofer.

I know the noise cuz back when I first got the amp I had the same issue and Outlaw exchanged the amp for me and I went with the XLR cables.

Scott told me to see if the noise was coming from all speakers and the sub (I cant hear it in the sub after turning the Outlaw EX sub on its face)but it is coming from the rest of the 7 speakers.

He also told me to plug the Audessey Mic back in, then remove it. I tried that and it had no effect on the noise.

I think my 5 year warranty is up, and I DREAD paying shipping for a 100 pound amp both ways for the repair......

I will be calling Scott again in the morning. Anyone else have any thoughts?

Check all your connections to make sure they do not have a stray wire to ground. Both the amp and the AVP should share the same common ground (as should the rest of the equipment). If the ground plane is different between the various pieces of equipment it allows current to flow across the ground and usually is the cause of the hum. I don't see a surge protector/voltage regulator in your profile. I don't subscribe to the need for voltage regulation but for lightning protection and to provide a common ground they are great. Inspect the ground connectors on the AVP and the amp assuming the AVP has a grounded plug. If it doesn't have a grounded plug, you may need one. Sometimes the ground in the receptacle isn't secure to both outlets. Try plugging an extension cord into one receptacle and powering both pieces of equipment from the extension cord. If the hum goes away the house circuit is suspect. Don't run this way but it is a good way to check the receptacle.

Disconnect all the inputs to the amp and turn it on. If the amp is the problem you should hear the hum. If no hum, then plug in one input at a time until you do hear the hum then check that cable by swapping it with another. If both have the hum then check the connector on the AVP and the Amp.

Profile updated, I do have a Monster Power 2600 for most of my gear. The TV, PS3, Toshiba HD DVD player, Wii and the Sub are all connected to a Monster Power bar 1100 I believe on a different outlet, same 20 amp circuit as the rest of the stuff.

Thanks for the troubleshooting suggestions. I will be trying to find the culprit soon. I believe the Marantz AVP does not have a grounding plug, its a 2 pronger only.

The weird part is everything was fine, it was sounding great and then while it was on the hum started.

Any piece of your equipment could cause the hum if it sees a different ground value. You could try plugging your 1100 into the 2600 to give all of the equipment the same ground source.

Cant, they are in different areas of the room.

Talked to Scott again today for 30 minutes. HUGE HELP! The good news is it is NOT the amp. I unplugged the centre channel XLR cable and turned on the Marantz and the 7700 only, and no noise from the centre speaker.

So, I unplugged everything except the XLR cables and speaker wires. No noise. Thats good, I think. I then plugged in the outgoing HDMI cable from the Marantz to the TV. I get the hum. I then tried it in the HDMI out #2, still get the hum. So, it looks like either the cable, or someting connected to the TV.

Thats all I got done today. I hope its just the cable, even though that will require snaking a new cable thru walls. Easier than a repair on the amp I guess. More troubleshooting tomorrow.....

I think your problem might be that you have two different isolated power supplies hooked up to different parts of your system. My guess is that as soon as you plug anything powered by the Powerbar to the Marantz it's going to start buzzing.

The 2600 has a grounding post according to the literature. If the 1100 has a grounding post (couldn't find anything that says it does)then you could run a wire between the 2600 and 1100 and see if that fixes the problem.

Otherwise you might be able to run a wire from the chassis ground of your TV to the post of the 2600. I'll have to say I'm not quite certain what will happen to your surge protection if you tie the isolated grounds together. In theory you'll be fine but it's probably a good question for Monster.

I had not thought of that EEman, however it was not an issue for the last several years with the 886. Any idea why it would do this 15 minutes after running the 7005?

I did spend another 56:00 on the phone with Scott today. What a great guy.

We think we finally figured it out; I unplugged all source components from the Powerbar 1200 and that didnt change anything. But when I unplugged all source components from the 2600 and unplugged the 2600 from the wall outlet, and plugged the amp and marantz directly into the wall, the noise/hum was "almost" non-existant. It was very, very, very, very faint.

So, either the two Monster Power units are conflicting each other, or the 2600 is no longer good. And of course, its past the 5 year warranty, so I guess I need to be another unit.

Any other thoghts on two Monster Power units causing issues with the other? I will run it by Scott tomorrow, or call Monster and ask them.

I think the 2600 just picked that moment to die. Most manufacturers have a pretty good idea how long their equipment lasts and adjust their warranty period accordingly.

Did you hookup of the 2600 and 1100 cause the 2600 to die prematurely? I doubt it. If the chassis were properly grounded then I'd think there's no problem running in this configuration. If not then I would have expected you to hear ground loop buzz well before now.

I also looked a little more into power conditioner operation ('cause I'm a nerd) and tying the chassis grounds together should not impact the surge protection.

Wouldn't hurt to get Monster's thoughts on the problem. They are the experts on their product.

I called Monster, and the guy did not really sound like a really knowledgeable tech, but who am I to judge. I explained it to him and he said it soundled like it took a hit, Although there were no storms in the area, or anything out of the ordinary. He said if I shipped the unit back, they would give me a discount on another.

I ended up ordering a Tripp Lite from New Egg, very reasonably priced and has a longer warranty than Monster. I wasnt looking for one of the really cool looking products like the top of the line Monster stuff (but it would look neat!), just something to protect my stuff.

He agreed that having the 2600 and 1200 hooked up at different outlets but same circuit, should not be an issue.

I agree that having both hooked up to the same circuit but different outlets SHOULD not be an issue but a loose screw on the ground terminal anywhere in that circuit could cause the problem. Tripp-lite makes good equipment and should easily handle your equipment. I would take another look at the circuit your TV is plugged into and make sure all the connections are tight since the hum is slightly present. Is the Tripplite big enough to handle all of your equipment?