user2429: I played a FIDE tournament recently and was surprised to see that some players had earphones on and were listening to music (or that's what it seemed like they were doing) while playing their games. One of my own opponents did this. 
Is this allowed as per FIDE rules? 

user16639: I think it's covered by 12.3b as it does make a sound, even though it may only be audible to the person using it.
12.3 b. Without the permission of the arbiter a player is forbidden to have a mobile phone or other electronic means of communication in the playing venue, unless they are completely switched off. If any such device produces a sound, the player shall lose the game. The opponent shall win. However, if the opponent cannot win the game by any series of legal moves, his score shall be a draw.

user4418: When this question was asked in April 2014 the question to be answered in deciding whether or not to allow this would have been "Can other people also hear the music?" If "Yes" then it is disturbing and not allowed. If "No" then no problem.
However, events, technology and the rules have moved on.
The FIDE Arbiters Commission publishes the FIDE Arbiters' Magazine twice a year. In the August 2016 edition it related the story of a visually handicapped player who used an earphone to relay moves. It reported:

The cheating method was simply an electronic earpiece that was
  actually a Bluetooth device. This was not noticed until the player had
  posted consecutive tournament results that were astronomically better
  than before. He scored only 50% at novice level, but then within a
  year, while still unrated he won a rated section 8/9, and then again
  scored 8/9 with a performance rating near FM-level.
These 18 games were fully analyzed, and he was caught with
  continuously high correlations to chess engines, especially Rybka.
  Therefore, he was asked to take chess testing. At first, he accepted,
  “naked if necessary”, but then he eventually declined, saying that he
  has stopped studying, and that his abilities have thus dropped off
  dramatically. All of these games have since been adjudged lost.

Now the FIDE Laws of Chess say this:

11.3.2.1 During a game, a player is forbidden to have any electronic device not specifically approved by the arbiter in the playing venue.
However, the regulations of an event may allow such devices to be
  stored in a player’s bag, provided the device is completely switched
  off. This bag must be placed as agreed with the arbiter. Both players
  are forbidden to use this bag without permission of the arbiter.

As arbiters we are warned to look out for these devices. Smart watches are usually banned. Old fashioned digital watches are still mostly OK. Earpieces are not. Of course all of these things may be permitted in certain lower level competitions with the arbiter's permission. But if you wear an earpiece because you have hearing problems you should first get permission from the arbiter or remove it during the game.
Wearing an earpiece to listen to music is definitely not allowed.

user1761: The closest thing which I could find in the FIDE Laws of Chess is

12.3 a. During play the players are forbidden to make use of any notes, sources of information or advice, or analyse on another chessboard
12.3 b. Without the permission of the arbiter a player is forbidden to have a mobile phone or other electronic means of communication in the playing venue, unless they are completely switched off. If any such device produces a sound, the player shall lose the game. The opponent shall win. However, if the opponent cannot win the game by any series of legal moves, his score shall be a draw.

However, I'm not sure if music from earphones would be considered as "source of information" or an "electronic means of communication". The competition rules may specify that any kind of electronic equipment is disallowed, and the arbiters have the right to arbitrate things like these as long as their decisions are not unfair or contradictory to the laws of chess.
But the arbiter cannot know whether it is music or someone reciting a chess book, so I understand if some people strongly object to arbiters allowing players to have earphones. At least I've never been to a tournament where using earphones was allowed.
Note that if other players can hear the sound from the headphones, it violates this rule:

12.6 It is forbidden to distract or annoy the opponent in any manner whatsoever. This includes unreasonable claims, unreasonable offers of a draw or the introduction of a source of noise into the playing area.


2429: <p>I played a FIDE tournament recently and was surprised to see that some players had earphones on and were listening to music (or that's what it seemed like they were doing) while playing their games. One of my own opponents did this. </p>

<p>Is this allowed as per FIDE rules? </p>
 16639: <p>I think it's covered by 12.3b as it does make a sound, even though it may only be audible to the person using it.</p>

<p>12.3 b. Without the permission of the arbiter a player is forbidden to have a mobile phone or other electronic means of communication in the playing venue, unless they are completely switched off. <strong>If any such device produces a sound, the player shall lose the game</strong>. The opponent shall win. However, if the opponent cannot win the game by any series of legal moves, his score shall be a draw.</p>
 4418: <p>When this question was asked in April 2014 the question to be answered in deciding whether or not to allow this would have been "Can other people also hear the music?" If "Yes" then it is disturbing and not allowed. If "No" then no problem.</p>

<p>However, events, technology and the rules have moved on.</p>

<p>The <a href="http://arbiters.fide.com/" rel="noreferrer">FIDE Arbiters Commission</a> publishes the <a href="http://arbiters.fide.com/fide-arbiters-magazine.html" rel="noreferrer">FIDE Arbiters' Magazine</a> twice a year. In the <a href="http://arbiters.fide.com/images/stories/downloads/2016/FIDE_Arbiters_Magazine_No_3_-_August_2016.pdf" rel="noreferrer">August 2016 edition</a> it related the story of a visually handicapped player who used an earphone to relay moves. It reported:</p>

<blockquote>
  <p>The cheating method was simply an electronic earpiece that was
  actually a Bluetooth device. This was not noticed until the player had
  posted consecutive tournament results that were astronomically better
  than before. He scored only 50% at novice level, but then within a
  year, while still unrated he won a rated section 8/9, and then again
  scored 8/9 with a performance rating near FM-level.</p>
  
  <p>These 18 games were fully analyzed, and he was caught with
  continuously high correlations to chess engines, especially Rybka.
  Therefore, he was asked to take chess testing. At first, he accepted,
  “naked if necessary”, but then he eventually declined, saying that he
  has stopped studying, and that his abilities have thus dropped off
  dramatically. All of these games have since been adjudged lost.</p>
</blockquote>

<p>Now the FIDE Laws of Chess say this:</p>

<blockquote>
  <p>11.3.2.1 During a game, a player is <strong>forbidden to have any electronic device</strong> not specifically approved by the arbiter in the playing venue.</p>
  
  <p>However, the regulations of an event may allow such devices to be
  stored in a player’s bag, provided the device is completely switched
  off. This bag must be placed as agreed with the arbiter. Both players
  are forbidden to use this bag without permission of the arbiter.</p>
</blockquote>

<p>As arbiters we are warned to look out for these devices. Smart watches are usually banned. Old fashioned digital watches are still mostly OK. Earpieces are not. Of course all of these things may be permitted in certain lower level competitions with the arbiter's permission. But if you wear an earpiece because you have hearing problems you should first get permission from the arbiter or remove it during the game.</p>

<p>Wearing an earpiece to listen to music is definitely not allowed.</p>
 1761: <p>The closest thing which I could find in the <a href="http://www.fide.com/component/handbook/?id=124&amp;view=article" rel="noreferrer">FIDE Laws of Chess</a> is</p>
<blockquote>
<p>12.3 a. During play the players are forbidden to make use of any notes, sources of information or advice, or analyse on another chessboard</p>
<p>12.3 b. Without the permission of the arbiter a player is forbidden to have a mobile phone or other electronic means of communication in the playing venue, unless they are completely switched off. If any such device produces a sound, the player shall lose the game. The opponent shall win. However, if the opponent cannot win the game by any series of legal moves, his score shall be a draw.</p>
</blockquote>
<p>However, I'm not sure if music from earphones would be considered as &quot;source of information&quot; or an &quot;electronic means of communication&quot;. The competition rules may specify that any kind of electronic equipment is disallowed, and the arbiters have the right to arbitrate things like these as long as their decisions are not unfair or contradictory to the laws of chess.</p>
<p>But the arbiter cannot know whether it is music or someone reciting a chess book, so I understand if some people strongly object to arbiters allowing players to have earphones. At least I've never been to a tournament where using earphones was allowed.</p>
<p>Note that if other players can hear the sound from the headphones, it violates this rule:</p>
<blockquote>
<p>12.6 It is forbidden to distract or annoy the opponent in any manner whatsoever. This includes unreasonable claims, unreasonable offers of a draw or the introduction of a source of noise into the playing area.</p>
</blockquote>
