Help with humming noise from Logitech Z560 THX

[dayg]

Hi all,

I had these speakers for only a short time. It was working great till today. I had to swap out a desk, and reconnect my PC and speaker system back to what I had before. However, now I'm hearing a constant humming noise coming from the subwofer. The humming persist even if I turn off my computer and the power on the Logitech control center. The only way to get rid of the humming is by unplug the main power of the subwofer.

Anyone had this happened before? How do I fix this problem? Thanks.

 

[AzNmAnJLH]

warranty issue

 

[Howard]

It sounds like interference, or more likely ground hum, is getting the best of your speakers.

Is your sub power cable laid parallel to any power cords? If anybody have to meet or cross, place them so they are perpendicular.

 

[Howard]

BTW, recheck all connections to see if you haven't switched anything around.

 

[acidvoodoo]

i'd check all the cables are secure. Same thing happend to me and turned out that one of the satellites wasn't fully pulled in

 

[dayg]

thanks for all your help. It's weird, but I dicsovered its the Helogen lamp that's causing it. How could that be? As soon as I turn off the light, humming goes away! For now, I have to work in near darkness. Dang it!

 

[Yomicron]

Make the power cord for the lamp isn't running parallel to the signal wire for the subwofer. If the two are parallel it will create a hum.

 

[dayg]

Yomicron,
Could you explain "running parallel"? I don't follow. Thanks.

 

[Yomicron]

Is the lamp's power cord laying next to the subwofer's cable?

Power cords should always cross signal cables at 90 degree angles.

 

[NewForumMember]

Hiya,

I have the hum and been tolerating it. I'll try some things with cords when the comps off. Too many fans to hear the hum if the computer's on...

 

[clicknext]

Hey I have a hum too but I can't hear it unless I turn off my computer since the fans usually cover it. And my comp isn't off very often when I'm in th room.

 

[dayg]

Strange, I'm a bit surprised many of you had this problem. Do you all have a Helogen lamp near the sub?

Yomicron,
I tried moving the Helogen Lamp(300W) away from the subwofer like (6 feet away) and plugged to a different location but in the same living room and yet the humming still there!!!! However, once I turned off the lamp, humming goes away. This other thing I discovered today, my lamp has 2 switches a low (150w) and a high (300w), it ONLY hums when the lamp is on low(150W). Humming goes away when the lamp is on high! Isn't this strange?

 

[NewForumMember]

The hum didn't change at all when moving cords around. It must be something else. I live in a 100 person apt. building. There could be stuff plugged in around this room making it happen. I bought mine around January 15 this year. Is that possibly near you twos purchase date?

that's pretty weird with the lamp dayg.

 

[Abem3]

I had the same effect on my main HT system with one of those stupid halogen torchiere lamps. The whole room is on the same circiut and whenever that lamp would turn on, I would get a horrible buzz through all of my gear. It's definately not the logitech's fault, and I'm guessing that the transformers or whatever in the lamps suck something fierce.

My advice is to get a new lamp!

 

[dayg]

Abem3,

Agreed. Thanks for the headsup. Lamp's gotta go...

 

[WheelsCSM]

I have had mine for over a year now, and they have hummed ever since I got them. I have lived in three different places with them and they hummed in every one. Not sure what it is, but usually it's not loud enough to bother me.