Pioneer Receiver, 5.1 setup w/ loud rhythmic clicking sound on all sources.

[Ender88]

The sound is constant and plays through all the speakers including the subwoofer. I have done a little troubleshooting but I am at a loss.

 

[Harvey]

Some possibilities come to mind:

1. Something that draws a lot of current is drawing the line down close to the point where the regulation of audio gear's power supply is marginal. Examples include a refrigerator, air conditioner, etc.

If you have an AC volt meter, measure the line voltage. It should be close to 117 volts AC.

Try unplugging other items on the same cicuit and/or try plugging the audio gear into another socket.

2. Some other electronic device is generating air or line borne interference, possibly in the RF band, that is interacting with the audio electronics. Examples would be a cell phone or cordless phone. For example, if it's a cordless phone, try moving the phone's base station to another point in the room.

3. Check your grounding. The shield in some cheap audio cables with RCA connectors can become damaged, especially at the connectors.

Try unplugging all analog sources. If the problem disappears, try re-connecting them one at a time until the problem returns. If that finds it, try new RCA cables.

If you have a phonograph turntable with a magnetic cartridge, it could be an easy point to introduce interference.

4. Again on the subject of grounding, if any of your audio components have two prong AC plugs, you may have to turn one of them over. Sometimes, you can actually feel an electric tingle when lightly running your finger over the metal surfaces of two piece of gear.

5. Yet again on the subject of grounding, are the ground lugs of your AC wall connectors connected to house ground? Some older installations have three wire plugs with only the two flat contacts connected.

If the ground lugs are all connected, are they properly returned to ground at the AC mains?

Hope that helps.

 

[Ender88]

Some possibilities come to mind:

1. Something that draws a lot of current is drawing the line down close to the point where the regulation of audio gear's power supply is marginal. Examples include a refrigerator, air conditioner, etc.

If you have an AC volt meter, measure the line voltage. It should be close to 117 volts AC.

Try unplugging other items on the same cicuit and/or try plugging the audio gear into another socket.

2. Some other electronic device is generating air or line borne interference, possibly in the RF band, that is interacting with the audio electronics. Examples would be a cell phone or cordless phone. For example, if it's a cordless phone, try moving the phone's base station to another point in the room.

3. Check your grounding. The shield in some cheap audio cables with RCA connectors can become damaged, especially at the connectors.

Try unplugging all analog sources. If the problem disappears, try re-connecting them one at a time until the problem returns. If that finds it, try new RCA cables.

If you have a phonograph turntable with a magnetic cartridge, it could be an easy point to introduce interference.

4. Again on the subject of grounding, if any of your audio components have two prong AC plugs, you may have to turn one of them over. Sometimes, you can actually feel an electric tingle when lightly running your finger over the metal surfaces of two piece of gear.

5. Yet again on the subject of grounding, are the ground lugs of your AC wall connectors connected to house ground? Some older installations have three wire plugs with only the two flat contacts connected.

If the ground lugs are all connected, are they properly returned to ground at the AC mains?

Hope that helps.

I have now tried Steps 1 to 3. I am not clear on what you mean in Step 4 and I have no way of knowing if the ground lugs as connected to the house ground... But the house was built in 2001 if that tells you anything. So far the only thing that stops the sound is unplugging which ever optical cable is being used for the current source but then of course I lose the sound altogether.

 

[Harvey]

I have now tried Steps 1 to 3. I am not clear on what you mean in Step 4 and I have no way of knowing if the ground lugs as connected to the house ground... But the house was built in 2001 if that tells you anything.

A house built in 2001 SHOULD BE up to current electrical codes for grounding... plus or minus unknown variables like the integrity of the builder and local building inspectors.

Two things you can check. For safety, do these in the right order.

1. To determine whether there is any voltage on a ground lug, use an AC voltmeter set to a range 220 volts or higher to measure whether there is any potential between ground lugs on two different AC outlets (not just two on the same fixture). If so, you have serious wiring problems.

2. Only after you check for any voltage on the ground lugs, set the meter as an ohm meter to see if the ground lugs on two different AC outlets are connected to each other. If they are, you should get a very low reading between them. Theoreitcally, it should be zero ohms, but even very large guage wire has a finite resistance.

So far the only thing that stops the sound is unplugging which ever optical cable is being used for the current source but then of course I lose the sound altogether.

Hmmm... Optical connections are electrically isolated so they shouldn't have grounding problems. Another possibility could be that the clicking sound is a "beat frequency" between two high frequency digital clocks oscillating at very close frequencies. The rhythmic clicking would be at the difference between the two frequencies, and the closer the two frequencies are, the greater the amplitude (loudness).

As I noted, above, you could get the same kind of beat frequency from an interaction between the local clock in your receiver and the clock in an unrleated, nearby electonic device such as a cordless phone. When I talk with one of my friends on the phone, I sometimes hear a click-click-click that appears and disappears as he walks around his livingroom.

Most digital gear is designed to sync and lock the clocks between external sources and an internal clock, but this could happen if the sources drop out of sync. Have you tried connecting the same external digital sources to another system? If they work with another system, it would suggest that the problem is in your receiver.

If it's not impractical, you could take your receiver to a friend's house, and test it with his/her sources and AC power.