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I have been noticing a strange audible electonic beeping coming out of the sub intermittently (now two different subs so it can't be a sub issue). Basically sounds like interference from my blackberry or some other radio interference going through the sub (and waking the sub from it's auto off state). I've tried plugging the sub into a different socket to no avail.


I'm thinking it might be my blackberry as I know when I keep my blackberry near my phone at work I get the exact same audible sound coming from the speaker in the phone.


Anyone ever experience this before or know of ways to stop it from happening?


I'm making the assumption it has to do with my BB but I've heard it at times when I didn't have my BB in the room so I'm not 100% sure!


Tx
 

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I used to have this with a sub that I owned. I wish I could give you an answer as to why it was happening. I noticed that when I had a cell phone "near" the sub it would sometimes get random sounds out of the sub. When the phone would ring I would get sound in the sub just before the phone rang. I had a very long cheap RS cable on there. I was thinking that the phone was inducing a current in the cable, then the sub made noise. Currently I am sub-less, so I didn't fix the problem.


If this is truly the reason a good shielded cable should fix the problem.


Anyone else have any ideas??


Good Luck.

Charlie
 

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A nearby GSM handset is usually the source of the "dit dit dit, dit dit dit, dit dit dit" signal that can be heard from time to time on home stereo systems, televisions, computers, and personal music devices. When these audio devices are in the near field of the GSM handset, the radio signal is strong enough that the solid state amplifiers in the audio chain function as a detector. The clicking noise itself represents the power bursts that carry the TDMA signal. These signals have been known to interfere with other electronic devices, such as car stereos and portable audio players.


The GSM data bursts used to report that a phone is in-region to a local tower are at 217Hz, and sent at full power. Once the tower reponds the phone modulates the power down to whatever is necessary to maintain a connection. This also happens immediately before a call is received.


You might try improving the shielding of cables, but unless you have really crappy cables at present I doubt you will cure this. Most times the interference is directly induced into the amplifier - in other words even if you unplug the audio cable feeding the sub you will still get the interference since the internals of the amp are still picking up the strong GSM signal.


I wonder whether the FCC has any view on this?
 
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