Yo consegui un codigo que creo que hace lo que pides:
Código HTML:
<select id="cancion" onchange="document.all.musica.filename=document.all.cancion.value;" name="Musica1">
<option selected="selected">Selecciona</option>
<option value="music/tema1.mp3">Tema1</option>
</select>
<br>
<object id="musica" height="44" width="70" align="middle" classid="clsid:22D6F312-B0F6-11D0-94AB-0080C74C7E95">
<param name="AutoStart" value="-1" />
<param name="Balance" value="0" />
<param name="DisplaySize" value="4" />
<param name="Filename" value="" />
<param name="Mute" value="0" />
<param name="SelectionStart" value="-1" />
<param name="SelectionEnd" value="-1" />
<param name="ShowControls" value="-1" />
<param name="ShowAudioControls" value="-1" />
<param name="ShowDisplay" value="0" />
<param name="ShowPositionControls" value="-1" />
<param name="Volume" value="0" />
<param name="AudioStream" value="-1" />
<param name="AutoSize" value="0" />
<param name="AnimationAtStart" value="-1" />
<param name="AllowScan" value="-1" />
<param name="AllowChangeDisplaySize" value="-1" />
<param name="AutoRewind" value="0" /><param name="BaseURL" value"value" />
<param name="BufferingTime" value="5" /><param name="CaptioningID" value"value" />
<param name="ClickToPlay" value="-1" />
<param name="CursorType" value="0" />
<param name="CurrentPosition" value="-1" />
<param name="CurrentMarker" value="0" /><param name="DefaultFrame" value"value" />
<param name="DisplayBackColor" value="0" />
<param name="DisplayForeColor" value="16777215" />
<param name="DisplayMode" value="0" />
<param name="Enabled" value="-1" />
<param name="EnableContextMenu" value="-1" />
<param name="EnablePositionControls" value="-1" />
<param name="EnableFullScreenControls" value="0" />
<param name="EnableTracker" value="-1" />
<param name="InvokeURLs" value="-1" />
<param name="Language" value="-1" />
<param name="PlayCount" value="1" />
<param name="PreviewMode" value="0" />
<param name="Rate" value="1" /><param name="SAMILang" value"value" /> <param name="SAMIStyle" value"value" /> <param name="SAMIFileName" value"value" />
<param name="SendOpenStateChangeEvents" value="-1" />
<param name="SendWarningEvents" value="-1" />
<param name="SendErrorEvents" value="-1" />
<param name="SendKeyboardEvents" value="0" />
<param name="SendMouseClickEvents" value="0" />
<param name="SendMouseMoveEvents" value="0" />
<param name="SendPlayStateChangeEvents" value="-1" />
<param name="ShowCaptioning" value="0" />
<param name="ShowGotoBar" value="0" />
<param name="ShowStatusBar" value="0" />
<param name="ShowTracker" value="-1" />
<param name="TransparentAtStart" value="0" />
<param name="VideoBorderWidth" value="0" />
<param name="VideoBorderColor" value="0" />
<param name="VideoBorder3D" value="0" />
<param name="WindowlessVideo" value="0" />
</object>