You could;

1) Try different makes of speakers until you find some that are not as
susceptible to the interference. Ones with metal cases might be better
shielded.
2) Move the speakers to a location further from the phones. Like placing
them on the floor under the desks.
3) Buy snap-on ferrite chokes from Radio Shack and put them on the audio
and power cables going into the speaker amplifiers.

The latest theory on the disappearing bee populations is that
electro-magnetic cell phone emissions are disorienting the bees. Makes
you kind of wonder doesn't it?

DougSlug wrote:

In my office we often experience instances of a "galloping" sort of buzz
periodically coming from the PC speakers near co-workers who have Cingular
GSM cell phones. A preliminary Web search turns up many instances of this
problem. My understanding is that these phones periodically communicate with
the network, and during these brief bursts the carrier is modulated at
around 200 Hz resulting is a clear, repeatable buzz pattern. How is this
buzz getting into the PC speaker amplifier, and, more importantly, how can
it be prevented?

Thanks,
Doug





--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P