I just got a 900 MHz DSS cordless phone, and I had the perfect spot
> for it, right on top of my tower computer case. But then I noticed
> that the manual says that the base unit must be placed away from all
> electronic equipment, including PCs, stereos, TVs, and microwaves.
> What is the reasoning for this? Could the magnetic fields generated
> by the speakers in the phone cause any problems?
Usually the problem is nothing more than radio frequency interferrence. Much like you get if you take a portable radio and get it too close to your computer or monitor.
I have run into some cases where routers or even computers rebooted when a portable phone transmitter is placed too close to them due to the RFI.