hear radio broadcast on the phone???interfere modem.

In such cases it's common to have a simple RF filter on the incoming phone line. I have one here.

In the UK BT will fit such a filter for you.

Graham

It's caused by the signal from the radio station leaking into your telephones and possibly the lines.

Listen until you hear a station ID, then call the station and ask to speak to the chief engineer about an interference problem. Be polite and they will help you fix the problem.

Geoff.

If the audio is intelligible, it is an AM station. Is your home hear one? If so, the phone company will usually install a filter for no charge.

Yes, that is possible and likely. Here is what often happens: an intermittent connection (usually one with some oxidation) is acting like a rectifier. A rectifier is a detector (demodulator) for amplitude modulated radio signals. Intermittent joints, splices, or connections can change with the phase of the moon or the amount of lint in your dryer.

I live a mile from a 5KW AM station and had problems with radio audio in the telephone. My phone jacks were wired with jacketed two-pair unshielded wires. One of the pairs was unused. It turns out the unused pair acted as an antenna and fed RF to the phone. The phone rectified the RF and you know the rest. My solution: ground the unused pairs close to the tie point of your incoming phone line's terminal block; a cold-water pipe is best. That fixed my interference problem.

Xmttrman

I live a mile from a 5KW AM station and had problems with radio audio in the telephone. My phone jacks were wired with jacketed two-pair unshielded wires. One of the pairs was unused. It turns out the unused pair acted as an antenna and fed RF to the phone. The phone rectified the RF and you know the rest. My solution: ground the unused pairs close to the tie point of your incoming phone line's terminal block; a cold-water pipe is best. That fixed my interference problem.

Xmttrman

Marslee-

The FCC did a study and found that 68 percent of phones tested at that time, would receive radio interference. I can't find the report, but did find a summary at:

In your case, the problem might be in a phone at another part of the house that you don't suspect. If not, it is likely to be a problem with the wiring as others have suggested.

Fred