[Aetae]

Да нет, я просто на работе какбэ)

<table id='music'>
 <tr><td>1</td></tr>
 <tr><td>к1</td></tr>
 <tr><td>2</td></tr>
 <tr><td>к2</td></tr>
 <tr><td>3</td></tr>
 <tr><td>к3</td></tr>
 <tr><td>4</td></tr>
 <tr><td>к4</td></tr>
 <tr><td>5</td></tr>
 <tr><td>к5</td></tr>
 <tr><td>6</td></tr>
 <tr><td>к6</td></tr>
 <tr><td>7</td></tr>
 <tr><td>к7</td></tr>
</table>
<script>
(function(){
  var rand, table=document.getElementById('music'), tr=[].slice.call(table.getElementsByTagName('tr')), i=tr.length;
  table=tr[0].parentNode; //ибо tbody итп
  while(i--){
    if(i%2) rand = Math.random()<.5;
    table.insertBefore( tr[i], rand ? table.firstChild : i%2 ? null : table.lastChild )
  }
})()
</script>

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