Absolutely. From the advent of radio broadcasting telephone lines were used for everything, audio and even DC signalling to control relays. All remote radio broadcasts used at least two lines. One for sending sound back to the station and a 2nd pair (telephone lines are a balanced pair of wires) for "cue" that came from the master control room to the remote site.

Since most transmitters were located outside of city limits, equalized telephone lines were used to send the sound from master control to the transmitter.

This was the most common and cheapest way to make the connection to the transmitter until the advent of inexpensive microwave equipment. And microwave links have a nasty habit of fading out during tropospheric inversions so they were actually not as reliable, over long distances, as a phone line with a backup phone line that took an alternate path. (first hand experience here. Ya I'm that old) :-)

Most people today have no idea how you transmit analogue audio faithfully and reliably over long distances, via wires. Telephone engineers figured it out over 100 years ago.