Oh Oh. RSP 1068 hum...

[flyboylr45]

My brand new Rsp 1068 started humming. I have had this processor for about 3 weeks. I moved a couple of things around, and found that you can only hear the hum when the component monitor output is connected. I think that the problem is that these wires run side by side to the tv power cable inside the wall. Is there anything I can do to eliminate this? Anything I can ground? I really don't want to take out the baseboards and fish a new wire and all that mess.

The power cable for the tv is a home depot generic 3 wire type. (Romex)

Thanks

[Kevin D]

Have you tried disconnecting the cable/sat feed(s)? That's the first step.

Kevin D.

[flyboylr45]

well, just narrowed it down. the hum is only present when the tv in on.

[Kevin D]

It still can be your cable. The TV is just a path for your ground loop to start. Is the TV plugged into the same outlet/circuit as the rest of your equipment? Anything else connected to the system but not plugged into the same outlet?

Just because the TV can turn the hum on/off does not mean the TV is at fault.

Kevin D.

[flyboylr45]

Everything is connected to the same outlet through a monster power center. The hum not only goes away with the tv off, but if I just disconnect the component cables from the tv, with the tv on, the hum goes away. I tried disconnecting the cable but it still hummed.

[flyboylr45]

Kevin D,

It is definetly the tv. I initially thought that since the component cables where next to the ac power cable fro the tv, the humming was originated there. I then ran a separate power cable to another ac outlet, and the hum was still there. Then I thought that maybe it was the component cables in the wall, so I ran separate component cables outside the wall, far apart from any power source and there was the hum again. This not only happens when it is connected to the rsp 1068 monitor out, but on all connectors including audio and composite video. I even tried grounding the rsp 1068, the monster power center and everything to no avail. It's got to be the tv. Got any suggestions?

(The tv is a plasma display from samsung)

[Kevin D]

Try removing the ground from the TV with a 3 to 2 prong adapter and let us know what happens.

Kevin D.

[Kevin D]

This didn't happen to start after you put the empty RCA connectors on the unused inputs did it?

Kevin D.

[flyboylr45]

No, I haven't put those in yet. :lol: I will try that. But just for info, what does that do and where can I get one? Radio Shack? Thanks

[Ferres]

No, I haven't put those in yet. :lol: I will try that. But just for info, what does that do and where can I get one? Radio Shack? Thanks

There is a theory that unused inputs attract RF noise. I think some companies sell a kind of rca plugs. :roll:

[chanlon]

My 1068 is currently getting repaired by Rotel for a humming issue.
You can check an earlier post of mine regarding my issue if you are interested. And it hums with the presence of component cables. Please note that this may not be the same issue

[Kevin D]

No, I haven't put those in yet. :lol: I will try that. But just for info, what does that do and where can I get one? Radio Shack? Thanks

The 2-3 prong adapter you can get at Walmart, Lowes, etc.. You plug the TV power into it and it only has the power lugs on the other side (no ground).

Can you elaborate how the romex is used for power? Outlet on one end, plug on the other, or does the romex go straight to the TV?

Kevin D.

[flyboylr45]

The Romex cable goes straight into the tv from the Monster Power center. The hum is still there even if it is plugged in on a separate socket. Well, the hum is stilll there when I use the original power cord and a different set of component cables that are not running through the wall. I messed a little with it yesterday and the hum is even present when I use an S-Video, and composite connection. Anything that goes directly from the tv to the Rsp- 1068 hums. I have the dvd player connected directly to the tv through the cables on the wall and nothing. Everything seems ok.

I noticed that this only happens with video connections. If I connect the audio outputs from the tv nothing happens.

[flyboylr45]

Ok Kevin D, ;x(

I would like to know one thing. Why does the cheater plug work? I bought a cheater plug for $.76 cents and the Hum is GONE!!!! :T Thanks alot for all your help. Please explain the reasoning behind it. I just don't get it. Thanks.

[flyboylr45]

bump

[Kevin D]

Ground loops are right there with UFOs and other hard to explain phenomenon.

The good news is you fixed the hum, but you didn't fix the problem. Many will argue that a cheater plug is patch that should only be done to isolate a problem. I don't agree with that, but if you can test some other solutions when you can you might be able to remove the cheater plug.

Why it works is the ground in electrical signals wants to find the easiest path to true earth ground. This is usually through the power cable attached to the unit. In your case it's easier for the system's ground to go through the video cables, through the TV circuits, and then through the TV's ground wire. This causes a hum as the ground path and power path are now different. Removing this option removes the hum.

The crazy thing is it still may not be the tv causing the issue! The true issue might be another device, some how grounded to the system, that only causes an issue when the ground of the TV is connected to the system. In your spare time you could disconnect everything from the system but the TV and pre-amp(power and signal) and see if you get the hum. If not, add each piece one at a time until it appears.

Just check again and make sure nothing is connected to any part of the system and plugged into a different outlet. I've seen cable/DSS cables, phone lines, network cables, etc do some crazy things. Even a subwoofer plugged into a different outlet (because of room layout) can ground through the sub cable, to the 1068, out the video wires, and into the tv's ground.

Could still be a problem in the 1068 (like Chanlon's), the TV, or anything else. It's up to you to decide whether you should sit back and enjoy your system now, or worry about the very minuscule issues that might arise (that I've never seen proof of) from using the cheater plug.

Kevin D.

[flyboylr45]

When I get back from this next trip, I will do more trouble shooting. What kind of problems could arise from the cheater plug?

[flyboylr45]

I did a little bit of trouble shooting. The hum is audible with the amplifier on but the processor and everything else except the tv off. When I turn the processor on, the noise is more audible. It doesn't go up and down with the volume knob, but it does go away with the unit in mute or the volume all the way down. I don't know if this is related, but the tv also has a small white line that goes from side to side on the bottom part of the screen. This is visible sometimes and I have only noticed it with the component inputs, never with the cable coax. Thanks.