what to do cordless phone amplifier problem

Hi,

I have mono amps where one of the two mono amps has intermittent interference from static which comes out of one of the speakers. I did a variety of tests to rule out as the source of the problem: the speakers, the preamp, the cd player, the speaker cable, and the interconnect cable. I also tried grounding the amplifier as well as power conditioner. I sent the amplifier back to the manufacturer and the manufacturer says the amp works fine.

Today, my wife tried to use the cordless phone in the downstairs bedroom and instead of getting a dial tone she got the sound of my stereo blaring through the cordless phone receiver. She then noticed that this same thing happened on the kitchen cordless phone too.

I assume that the problem with phone picking up my stereo signal is linked to my intermittent static issue.

Since its happening on two separate cordless phones on two different floors of the house(same phone number though), should I be calling a electrician or the phone company to check out the phone lines?

The problem does not occur continuously. The phenomena lasted for about 10 minutes.

Any thoughts?

Michael