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jjb
2006-03-05, 11:12
Hi: I am trying to set up my slimdevice but am getting a lot of background static. I have two speaker sets that I am working with (and i realize they are quite low-end....)

* the ihome alarm clock (http://www.ihomeaudio.com/products.asp?product_id=10015&dept_id=1003) through its audio in line. i then hit the "ipod" button (without an ipod being present) on the alarm clock and its LCD displayed AUX and static started coming out of the speakers.

2. the insignia bookshelf stereo (http://www.bestbuy.com/site/olspage.jsp?CategoryID=cat03055&id=1099393710467&skuId=7016105&type=product&DCMP=KNC-TLC&ref=25&loc=MSY) through its audio in line. I then hit AUX and got the static.

Both give me a small background noise if I have the Aux option selected and the cables plugged into the stereo on one end but nothing on the other end. The background noise goes away if I plug the cables into my ipod and it will play music fine. The background noise intensifies if I plug it into the slimdevice, without having my computer on nor the slimserver software running. If I boot up my computer it will play music, but the background static will still be there.

I currently have about 2 or 3 different wireless internet networks being broadcast through my apartment from neighbors / city living.

Any thoughts how I can eliminate this static?

Kind regards
Janet

Mark Lanctot
2006-03-05, 11:40
Sounds like the cables are faulty. They are probably picking up electromagnetic interference (EMI).

Is it a hiss (high-pitched static) or is it a hum (low pitch)? If it's a hum, it's what's known as a ground loop. The fact that it goes away when you plug your iPod in reinforces the ground loop argument - the iPod is battery-powered while the Squeezebox is powered by household power.

In either case, replacing the cable with a better shielded one should help. Don't go overboard, you can get some incredibly expensive cables - you don't need those and will not get any benefit from them. But you do need better shielding.

Solving ground loop issues is unfortunately very complicated and is often impossible to solve. Solving EMI issues is a little easier.

You may want to experiment around with cable placement. Always cross power lines at 90 degree angles, don't follow them for more than 6 inches. Also slightly adjusting the placement of the cables can help as it may be exposed to less EMI even a few inches away.

Does the static/hum get louder if you touch the unconnected end of the cable? This is indicative of a ground loop as well.

jjb
2006-03-19, 18:20
Thanks for the feedback. I apologize for the delay in getting back to you - I got swamped at work, finally got a chance to look at this again, and all the static miraculously went away somehow in the meantime. Not sure why, as I'm not doing anything differently (that I know of...), but now it all works!

Thanks
Janet