The most common and most likely answer to this crossword clue is the 9 letter word EARPHONES
I've seen this crossword clue in The Times
E
A
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P
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More clues leading to the result EARPHONES
- Listening device lawman refines over time
- Listening devices from back of one shop near Barking
- Doc’s western pal? He’s recruited about two auditors
- One phrase reformatted for source of stereo sound
- Audio equipment distorted one phrase
- Western lawman perfects listening equipment
- Listening devices one sherpa moved around
Buddy explains!

The straight part
We know that "Listening device" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case listening device = earphones.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does EARPHONES mean?
EARPHONES noun- A pair of small loudspeakers worn inside each outer ear or covering all or part of the ear, without a connecting band worn over head.
- A transducer that converts electric signals into sound and is held near the ear, especially as part of a telephone; an earpiece or headphone.