Weird radio sound

Occasionally when I start or cut off the engine my radio, tape player or CD player (even if they aren’t on) will make a weird sound. Actually it wouldn’t be a weird sound if I was riding on a crow. That is what it sounds like (CAW-CAW-CAW). Sometimes only three caws but other times 10 or 15 times. The Toyota service dept said they had no idea what it could be unless they could hear the sound, needless to say it would never do it for them. Any idea what this could be? It has been doing it for about a year, so it must not be anything serious, but it’s driving me crazier than I normally am. Thanks for your help.

Are these factory installed units or a DIY job?

It was factory installed. Any Ideas??? Thanks.
Just remembered, there was a recall on the radio when I first got the car so I took it to the Toyota dealership and they installed the one in the car now.

Some of these units will do this if there is a bad ground to the speakers or to the unit itself. There is also a bleed through effect if the volume control is weak or malfunctioning. Try turning off the radio, CD or tape player before you start or shut off the ignition. If the “crow” goes away the volume control on one of the units is probably weak. Dealerships are normally clueless anyway so a good stereo installation shop should be able to sort it out for you.

Sounds likely, once there was a loud POP when I turned on the radio. I’ll try to locate a stereo installation shop. Is that how they would be listed in the yellow pages? I appreciate the info.