hdmi buzz

[moreira85]

I got a new yamaha rx667 and now running all hdmi. I notice a light buzz coming through
The speakers. It sounds like a bee hive or one of those lights that buzz in really old basements and really only noticeable from a meter away. It doesn't get louder as I increase the volume. if I turn off the receiver with external amp still on I still hear it. Any time I unplug the hdmi out to the,tv it goes away. If I switch to optical theres no buzz. I did a Google search on hdmi buzz and found others have the same issue when connecting hdmi to tv. Thoughts?
@Adam tried troubleshooting w me last night. I may unplug all the preouts and run a speaker through the receivers terminal to see if the amp is causing the buzz.

 

[TLS Guy]

I got a new yamaha rx667 and now running all hdmi. I notice a light buzz coming through
The speakers. It sounds like a bee hive or one of those lights that buzz in really old basements and really only noticeable from a meter away. It doesn't get louder as I increase the volume. if I turn off the receiver with external amp still on I still hear it. Any time I unplug the hdmi out to the,tv it goes away. If I switch to optical theres no buzz. I did a Google search on hdmi buzz and found others have the same issue when connecting hdmi to tv. Thoughts?
@Adam tried troubleshooting w me last night. I may unplug all the preouts and run a speaker through the receivers terminal to see if the amp is causing the buzz.

You have a ground loop between the TV and the rest of your system, due to the grounds at the two outlets being at different potential.

Either run an AC cable from the TV to the rest of your system, or lift the TV ground.

This is a common problem. My TV power comes from the UPS in the AV rack and the AC feed runs in conduit to the TV.

I suspect your receiver is ungrounded, but your power amp is, is that correct?

 

[moreira85]

buzz

I unplugged the pre outs n ran the speakers off the receiver instead of amp and it was perfect with hdmi. Plug the preouts back in w hdmi and buzzes.
I then unplugged hdmi and used optical w the preouts n amp and no buzz.
So I get the issue when I use hdmi for sound with preouts. It is only noticeable if I put my ear near the speaker. It sounds like its distorted like the sound is being semi scrambled.

 

[moreira85]

You have a ground loop between the TV and the rest of your system, due to the grounds at the two outlets being at different potential.

Either run an AC cable from the TV to the rest of your system, or lift the TV ground.

This is a common problem. My TV power comes from the UPS in the AV rack and the AC feed runs in conduit to the TV.

I suspect your receiver is ungrounded, but your power amp is, is that correct?

My tv is plugged into the power conditioner to begin with.

 

[TLS Guy]

My tv is plugged into the power conditioner to begin with.

In that case the power amp is the source of the loop. Does you power amp have a two pin or three pin AC plug. In general grounding power amps causes nothing but trouble. I never ground that which is standard professional practice.

 

[moreira85]

You have a ground loop between the TV and the rest of your system, due to the grounds at the two outlets being at different potential.

Either run an AC cable from the TV to the rest of your system, or lift the TV ground.

This is a common problem. My TV power comes from the UPS in the AV rack and the AC feed runs in conduit to the TV.

I suspect your receiver is ungrounded, but your power amp is, is that correct?

What do you mean by receiver ungrounded? 3 pronged on the plug?

 

[TLS Guy]

What do you mean by receiver ungrounded? 3 pronged on the plug?

OK to sort this out, we need to know which units have three pin plugs and which have two.

The best practice is to ground preamps/AVRs/mixers, but not the power amps they are connected to.

You have proved that the actual source of the loop is you receiver power amp connection, so now we need to know which units have three pin plugs and which have two.

If your receiver has a three pin plug and so does the power amp, that frequently causes the problem you describe and worse.

 

[moreira85]

Amp 3 prong
Tv 3 prong
Dvr sat box 3 prong
Behringer eq 3 prong
Receiver 2 prong
Dvd 2 prong

All plugged into belkin which also has 3 prongs.

Sub has 2 prongs plugged into its own wall outlet but I unpluged it from wall for now to eliminate that.

 

[TLS Guy]

Amp 3 prong
Tv 3 prong
Dvr sat box 3 prong
Behringer eq 3 prong
Receiver 2 prong
Dvd 2 prong

All plugged into belkin which also has 3 prongs.

Sub has 2 prongs plugged into its own wall outlet but I unpluged it from wall for now to eliminate that.

That is what I suspected.

Just for one last check, disconnect you TV Sat box. If it makes no difference, then the problem is an ungrounded receiver and a grounded power amp. That is a bad situation.

First bond the the chassis of the receiver and power amp, with No. 4 copper wire.

If that does not solve it post back, but the solution will be to ground the receiver and lift the power amp ground.

 

[moreira85]

That is what I suspected.

Just for one last check, disconnect you TV Sat box. If it makes no difference, then the problem is an ungrounded receiver and a grounded power amp. That is a bad situation.

First bond the the chassis of the receiver and power amp, with No. 4 copper wire.

If that does not solve it post back, but the solution will be to ground the receiver and lift the power amp ground.

So i am connecting a copper wire from receiver to amp to confirm?
Also I unplugged the cable box and still no change

 

[TLS Guy]

So i am connecting a copper wire from receiver to amp to confirm?

Yes, and big fat one. I have to go out now and will explain later the way I do it.

 

[moreira85]

grnd

I Attached just a small copper spkr wire to ground on receiver to amp and no change. I'm out to get no. 4 wire now.

 

[Adam]

Do you have any speaker wire around? You could try that. It's a function of cross-sectional area, so connecting up some speaker wire should work fine (I'm guessing that you're using 18-gauge or thicker).

Where did you attach the wire on the chassis?

 

[moreira85]

grnd

I attached it to the terminal on back of receiver and then the screw on the left side of the emotiva.
I also noticed if I turn up the volume the buzz Definetly gets louder

 

[moreira85]

Gotcha!

After lots of troubleshooting here is the issue. Everything is hooked up e hdmi n there's a buzz. I unplug the sub cable from the pre put and it is dead silent. Here is the kicker, the sub is turned off and unplugged yet when the sub cdble is in sub 1 or 2 pre out it buzzes?

 

[TLS Guy]

After lots of troubleshooting here is the issue. Everything is hooked up e hdmi n there's a buzz. I unplug the sub cable from the pre put and it is dead silent. Here is the kicker, the sub is turned off and unplugged yet when the sub cdble is in sub 1 or 2 pre out it buzzes?

That is a strange one!

Now we need to know if you have a bad cable or if it is the sub power supply causing trouble.

Disconnect the cable at the sub and and short the plug with a wire and clips.

If there is still hum you have a bad cable. If it only hums when connected to the sub, then the sub is causing trouble probably somehow feeding rf interference back to the receiver.

The power supplies and electronics of sub plate amps are just awful. It always amazes me they work at all for any length of time. Talk about pinching pennies left right and center.

One thing I would never own under any circumstances is a commercial sub!

 

[moreira85]

troubleshoot

I will try that in a bit and post back. The sub is not even plugged into the wall. That cable however starts as a pre out at the receiver into xlr at behringer , out as xlr to sub and plugs into sub as 75 ohm sub cable. So it could be either of those cables.

 

[highfigh]

I will try that in a bit and post back. The sub is not even plugged into the wall. That cable however starts as a pre out at the receiver into xlr at behringer , out as xlr to sub and plugs into sub as 75 ohm sub cable. So it could be either of those cables.

You said you unplugged the cable box- power cord, or coax feed? Disconnect the cable feed and see if the noise goes away. If it does, call the cable company and tell them to ground their feed, as required by the National Electric Code.

 

[TLS Guy]

I will try that in a bit and post back. The sub is not even plugged into the wall. That cable however starts as a pre out at the receiver into xlr at behringer , out as xlr to sub and plugs into sub as 75 ohm sub cable. So it could be either of those cables.

That thickens the plot enormously. You have a floating line. These are highly problematic and we need to know the exact details. I suspect this floating line is constructed improperly.

This just shows that in these types of posts we need the greatest detail.

Our replies will only be as good as the details of the post.

 

[Adam]

Yep, the plot just keeps getting thicker, doesn't it?